Subtitle: Construction methods and procedures to prevent wetting no matter where you interrupt it (2-story wooden building, slate assuming/DIY renovation)

Hello, this is DIY Renova.

In this article, we will explain how to "close rain in the middle" to prevent rain from getting wet when rain comes during "demolition or replacement" of the roof, down to the level of handling of a single nail, depending on the pattern.
This time we will mainly be taking cosmetic slates (colonials, etc.) as examples, but most of the materials are the same structure and overlap, so I think it can be useful in some way.

"How to dismantle the slate itself" is summarized in a separate article, so here we will focus on "waterproofing at the moment when work is interrupted."

The target is Japanese wooden detached houses (up to 2 floors). We also include engineered numerical guidelines and criteria for judging the results so that they can be reproduced even in a completely DIY format. We will also provide a clear description of the minimum points to follow regarding laws and safety. The article is long, but I have compiled it with the aim of creating a structure that allows you to take action without hesitation based on this article alone.

If you're wondering "How much renovation or remodeling can I actually do on my own home?" or "Where should I even start?", please visit this page. If you're looking to learn more about specific renovation processes or construction details, don't miss this page as well!

So, here you go.

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Assumptions and general concepts

• Estimated materials: "Existing = decorative slate," "Print = base = wide base plate (often around 12mm thick)" "Roofing = modified asphalt (both adhesive and non-adhesive)"
• Purpose: "Even if you stop working halfway through, the inside will not get wet." The three key points are: "Make sure the drainage path is continuous from top to bottom," "Layout order to prevent reverse water (water entering upwards)," and "fixing methods that do not withstand the wind."
• Safety and Laws (Japan): "Scaffolding + handrail + full harness" is the basics. Even if you are doing DIY, a fall can be life-threatening. Securely attach the anchor to a strong structural material, and manage the slack in the rope (a general guideline is to use a product with a strength of around 12kN. This is a guideline for supporting the load of a human fall, and cannot be replaced with a simple screw fastener).
  Also, some slates before 2006 contain asbestos, so if you have any doubts, stop the work and consult a specialist contractor following the guidance of the local government in charge (cutting, crushing, or scattering is strictly prohibited).
  Waste materials are separated according to local government rules and thoroughly cured to prevent them from scattering or falling.

We will explain the details by taking into account the material level and handling of a single nail so that you can choose the most suitable rainbow stop depending on the "stage" of "how far the demolition progressed."

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Assumptions and basic principles (align the axis of judgment first)

Three principles for rain closing

1. "Continuing the flow of rainwater from top to bottom"
   All the overlapping is to make sure that the water is won by the water and the water is not created, and the most important thing is not to create reversed water.
2. "Hold on to the surface and don't give in to the wind."
   The sheet is not pulled using only eyelets, but is "fixed" with a stove and a screw with a washer.
3. "Priority is given to detail at the edges, through areas, valleys and walls."
   Water leaks occur not from within the plane but from the edges and from the fights. On days when there is not enough time, we will finish the edges rather than the surface before leaving.

A guide to numbers (the minimum amount even amateurs can't miss out on their judgment)

• Approximate wind pressure: Speed ​​pressure q≈0.6×V² (kN/m², V is m/s)
  Example: q≈0.24kN/m² (approximately 24kgf/m²) at V=20m/s. A single 1.8 x 3.6m blue sheet will give approximately 155kgf of force applied to the entire surface. Therefore, "surface fixing" is essential.
• Estimated roofing fee:
  Gradient 3/10 or more → horizontal stacking of 100mm or more, vertical joints of 150mm or more.
  Gradient less than 3/10 - 150mm or more horizontal stacking, 200mm or more vertical joints.
  It is safe to add 50 to 100mm more to the edges (buildings, valleys, ves) than the above.
• Rainfall sensitivity adjustment: 10mm/h puts a load on areas of the roof that are prone to "swelling". It is important to avoid valley-like sagging in the sheet and guide the waterway to the eaves.

Consideration for safety, laws and asbestos (Japan)

• When working at high altitudes, please assume scaffolding, handrails, full harness, and master rope.
• Slates before 2006 may contain asbestos. If you have any doubts, do not cut, crush or polish, and consult a specialist contractor according to the guidance of your local government.
• It is essential to prevent waste materials, nails, and dust from scattering (flame-retardant mesh sheets, etc.) and to consider the neighborhood.

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“Rain stop in the middle” pattern classification and selection by demolition progress

Patterns for progress (stages 0-5)

The etiquette for stopping the rain gradually changes depending on how far the demolition has progressed. At each stage, we will summarize the following in the following order: "Purpose → Risk → Policy → Procedure → Check → Quantity Estimate → How to Return the Next Day."

Stage 0: Before demolition (preparation and initial treatment)

• Purpose: Create a system in advance so that even if rain comes right after the demolition begins, it can reach a "temporary water stop" within an hour.
• Main risk: It takes time to start, and the edges are exposed to the rain without finishing.
• Policy: Rafter core marking and “immediate response to surface fixing materials”.
• Procedure (material level)
  1. Scaffolding, flame-retardant mesh sheets and main rope have been installed.
  2. Find the rafter core from the roof and draw chalk lines on the ridge, verge, and eaves.
  3. Cut the bars to the required size and make a folding edge of the blue tarp (double layer to prevent tearing) in advance.
  4. The screws with washer are not placed casually on the roof, but are divided into small pieces into waist bags.
• Check: Are the screws configured to activate the rafters? Alarm set 90 minutes before withdrawal.
• Quantity guide: 2-3 3.6 x 5.4m sheets, 20m total of 20m strips, 200-300 washer screws, 2-3 rolls of butyl tape.
• How to return the next day: Store the materials without exposing them to the rain. Butyl maintains its adhesion by keeping it warm in the shade in the summer and in the winter.

Stage 1: Remove only the metal ridge and snow stopper fittings

• Purpose: To stop water from flooding through holes in the wing and metal fittings.
• Risk: Reverse water from horizontal joints and nail holes in the building. The snow-repellent base tears the sheet.
• Policy: "Must the points + only the building is protected in one flow."
• procedure
  1. All snow stoppers were removed first. Seal the removed holes with butyl.
  2. Remove the metal and pierced boards. The nail hole in the piercing is also a point sticker.
  3. Cover the ridge with a blue sheet from the water side in one direction, with overlapping layers of 150 mm or more from above the water to below the water.
  4. The seat is fixed using crosspieces and washer screws at a pitch of 300mm at the ridge core, verge, and eaves.
• Check: Are there any overlapping directions reversed at any one point/Does the sheet valleys not appear?
• Estimated quantity: 1 roll of butyl, 6 to 8 m of crosspieces, and about 100 washer screws.
• How to put it back the next day: Inspect the folded part for tears so that it can be reused even when flipping the sheet.

Stage 2: Unsubmitting the slate on one side

• Purpose: Stop water from exposed field with a "face" and then use a sheet to protect it secondary.
• Risk: Shower showers hit directly from Noji/adhesive roofing devices.
• Policy: "Adhesive roofing (exposure-allowable type) → Butyl terminal reinforcement → Sheet from above."
• procedure
  1. Cleaning the ground floor (sand, iron powder, nail scraps) → wipe dry.
  2. Sticky roofing is laid out from underwater. Horizontal stacking 100-150mm, vertical joints 150-200mm. Crimp with a roller.
  3. The ends are made of butyl and have a "Z-shaped" face seal (a fold-back type that prevents reverse water from breaking through).
  4. Secondary protection with blue tarpaulin from above. The side edges are fixed with slats.
• Check: Is the joint a "slanted" / Do you feel the sticky touch on the device with your fingertips (do the float again).
• Quantity guide: 1 roll of roofing (20m) is effective 17-18m², 1 roll of butyl, 1-2 sheets.
• How to put it back the next day: Wipe the dirt off the roofing surface → Continue with the next row.

Stage 3: More than half of one side has been removed

• Purpose: Strengthen “face-fixed splits” and end details due to increased wind loads.
• Risk: Peeling off or breaking with just one large sheet, intrusion from the kerabas and wing.
• Policy: "The sheets will be divided into 2-3 sheets," "Water will be returned in a temporary building," and "Water will always be completed."
• procedure
  1. The adhesive roofing is extended to the bottom of the water (eaves) to ensure waterproof surfaces.
  2. Cover the kerabas with a temporary sheet metal with L bent, and press the top edge with butyl + airtight tape.
  3. The building is covered with a simple temporary hatch (flat plate folded) and the joints are 150mm or more plus butyl.
  4. The blue tarps are stacked in the flow direction and covered with 2-3 sheets, and each sheet is fixed on the surface with a stove and washer screw (300mm pitch).
• Check: When stacking the split sheets, make sure to make the upper stream stand out, and there are no particular screws loose on the burr side.
• Quantity guide: 5-8m temporary sheet metal (Keraba/Building), 2 rolls of butyl, 2-3 sheets, 200-300 washer screws.
• How to put it back the next day: The order in which the sheet is removed is "underwater → above water." Replacing the edge tape if it gets dirty.

Stage 4: Just before the complete removal (close to exposed areas on both sides)

• Purpose: To advance "all-circumference details" that prevent water leakage from spreading on both sides.
• Risk: Simultaneous damage to reverse water and strong winds at the building, valley, and walls.
• Policy: "One layer of adhesive roofing on the entire surface + a temporary drainer with a full circumference."
• procedure
  1. Remove the ground from the possible area at once and remove sand and nail debris.
  2. Adhesive roofing is laid out across the entire surface. The building is set up on one side, and the other side is over 100mm.
  3. A temporary drainer (galva) is passed through the eaves and fixed to the rafter core at 200mm pitch using EPDM washer screws.
  4. The valley is laid out with temporary valley sheet metal, and both edges are sealed with butyl.
  5. When facing the wall, hold the device with 100-150mm up and airtight tape.
  6. The seats are doubled from above and over the building.
• Check: Is there a "top win" all around? / Is the "stagger" effective at the ridge and valley joints?
• Quantity guide: 2-3 roofing rolls, a total of about 20m of temporary drainage, temporary valley and temporary building, 3 rolls of butyl, 300-400 washer screws.
• How to restore the next day: Go to the next step before the adhesive becomes weakened by UV rays. For surface contamination, wipe dry and re-crimp.

Stage 5: Nearly both sides have been removed (final temporary water stop stage before finishing)

• Purpose: Create a temporary roof that can survive long rain and strong winds.
• Risk: Intrusion from all areas/loose temporary spurts.
• Policy: "Full-over adhesive roofing + full-circumference temporary sheet metal + double sheeting + indoor secondary protection."
• procedure
  1. Sticky roofing is continued throughout the entire surface and around the entire area. The ends are made of butyl and are sealed continuously.
  2. Temporary sheet metal is placed in the eaves, keraba, buildings and valleys, and the joints are over 150mm.
  3. The blue tarp is in two layers across the building. Each layer is fixed with a separate bar line, and the layering between layers is also superior.
  4. It is a policy inside the room and is subjected to double mist intrusion through the clear view of the Nojime.
• Check: No screws returned/No sagging valleys in the sheet/No layered reversal.
• Quantity guide: 3 or more sheets, 25-30m sashes, 400 washer screws, 3-4 rolls of butyl.
• How to return the next day: Dismantle from the outer circumference to the inside → Whenever you remove the temporary sheet metal, make sure to temporarily seal the device with tape (the principle is to "close at the edge when the edge is opened").

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"Rain closing in the middle" Weather pattern classification and how to choose

There are generally four types of interruption in work: Use it according to time and weather.

1. "A break, lunch break, 1-3 hours of departure"
   → Focusing on "blue sheet + temporary bar + washer screw fixing". Tape aids for valleys and walls.
2. "The possibility of showers across the sun (evening to the next morning)"
   → "Temporarily completes the adhesive roofing to be exposed and waterproof" + A sheet from above to protect against UV rays and wind.
3. "Suspend a few days to a week"
   →They are "underwater" every day using the strip technique (all streets) that separates the work belts. Water-retaining reinforcement with temporary sheet metal and butyl for each part.
4. "High wind speeds and heavy rain are expected due to the approaching front lines and typhoons."
   → "Return to field and complete adhesive roofing + temporary draining hardware". The sheet is double-layered and fixed to meet the guidelines for wind load calculation.

Simple criteria for choosing:

• If the rainfall probability is 40% or higher and the forecast rainfall rate is 10mm/h or higher, choose "2" or higher (even a short period of time, it is safe to ensure waterproof surfaces with adhesive roofing).
• If the expected wind speed is 15m/s or more (in a 20m/s class), the seat alone will be increased to an increased risk, and if possible, the fixation will be strengthened, and the seat will be upgraded to "2" or "4".
• After 1.5 hours before sunset, we decided to give priority to "complete the rain that has already been removed" without increasing the opening halfway through.

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Preparation: Required tools and materials (for link insertion)

Here are some of the things that "have this improves reproducibility." Product names will be listed as a general name. Please check the specifications yourself when purchasing.

• Blue tarp (#3000 or more, eyelet reinforced type)...Example: Size 3.6 x 5.4m, etc.
• Temporary fastening bar (recommended with rafters of about 2x2 or 30x40 or dry materials)
• Wooden screw with washer (with EPDM washer, 4.5 x 45 to 5.5 x 50 mm, selected based on thick and joist position)
• asphalt roofing

How to choose a roofing, where to buy and how to buy [DIY renovation]

• Butyl waterproof tape (one and both sides)
• Airtight waterproof tape (non-woven fabric/film, wind and rain support for stacking)
• Temporary sheet metal for valley/keraba temporary drainer (0.35-0.5mm galvalume, etc., ready-made or folded product)
• Roofing roller (crimping)
• Find a choke line and base for marking (If you can pick up the rafter core position from the bottom, it will be securely fixed)
• Full harness, lanyard, temporary master rope (horizontal lifeline)
• Flame-retardant mesh sheet (outer scaffold)
• Rain gutter curing (temporary filter formation using fallen leaf net or sponge)

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Basic engineering principles (minimum mathematical formulas that are effective for judgment)

• Estimated drainage amount: The approximate surface flow rate per unit width of the roof surface is "rainfall intensity i (m/s) x roof projected area A (m²)".
  For example, if the rain is 10mm/h (=2.78×10⁻⁶ m/s), and the width is 3m x the flow-down length is 5m, Q≈2.78×10⁻⁶×15=4.17×10⁻⁵ m³/s (approximately 0.15L/min). At first glance, it may seem like a little, but if you gather instantly in the "slack" part of the seat, it will cause water leakage.
• Approximate wind pressure: Speed ​​pressure q≈0.6×V² (kN/m², V is m/s). q≈0.24kN/m² (=approximately 24kgf/m²) at V=20m/s. This is a calculation that a force equivalent to approximately 155kgf can be applied to the entire surface on one 1.8 x 3.6m sheet. This is why it is necessary to fix the eyelets without concentrating them on one eyelet.
• Reasonable stacking fee: Water is from top to bottom. If the stacking allowance is 100mm and the roof slope is 3/10 (approximately 17°), there is a certain amount of room for capillary and wind pressure backflow. The gentler the slope, the more stacking fees will be (e.g., if it is less than 3/10, it is estimated to be 150mm or more). The "layer direction" always looks like a step above the water to below the water.

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Pattern 1: For a break to a few hours, go to "Blue sheet + temporary sash + washer screw"

In a short period of time, the key is to balance "speed" and "certainty."

procedure

1. "Minimize the open area"
   Do not open the valleys, walls, or around the top light if possible. This is because it is a part with a high risk of rain.
2. Create a "receiving" below the water (below side)
   Place temporary timbers along the top of the eaves fascia and secure them to the field base (eave joists/rafters) using washer screws. The pitch is approximately 200-300mm.
   Fold the hem of the seat back into the "receiver" and fasten it with a tacker, then press it down with a sash. This makes it less likely to turn over even in headwinds.
3. Sheet expansion
   Spread it out from below the water to above the water, and the top edge of the seat is long enough to exceed the ridge. The top side of the water is also pressed with a stove and washer screw. It's an image that doesn't rely solely on eyelets, but rather on the surface.
4. Side end (breast) treatment
   Since the burr side is prone to wind, the rails are also run parallel to the side edges, and the washer screws are fastened at 300mm pitch. If there is a fight with the exterior wall, apply butyl tape to the exterior wall, fold the edge of the sheet and press it together.
5. Securing rain roads
   When a valley-like groove forms on the sheet, water accumulates, so the bars are positioned diagonally to guide the water to the eaves.
   If there is any leaf litter or other waste in the gutter, it will overflow, so clean it before you work.
6. A little trick for each part
   • Immediately after removing the existing ridge sheet metal: Place the rails on the ridge core and cover the sheets separately on both sides (use two sheets is also effective).
   • The existing snow shielding brackets must be removed first (if left the sheet is left, the seat will break). The nail holes in the removal marks will be pre-treated with tape described below.

Failures and workarounds

• If the seat is "pushes around" it will tear with the wind → "Let it sagg slightly + hold it down with a side."
• The rope is attached using only eyelets → Directly leads to local breakage. Always use the surface fixing of the slat and washer screws.
• Water will spin behind the eaves → Always bring the hem out. Do not turn the fascia back.

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Pattern 2: Day-straddled showers are "temporarily completed with adhesive roofing exposed waterproofing"

If you are going to go through the night, it is more reliable to make a "surface waterproof" first rather than a blue tarpaulin alone before protecting it with a seat.

Concept of materials used

• Adhesive roofing that clearly states "high heat resistance" and "exposure allowed ◯ days". The roof surface temperature in the summer can be above 70°C (even above the galvae). Be sure to check the upper limit of the temperature listed.
• Since the adhesive strength differs greatly in product adhesion, we assume that butyl tape is auxiliary at the edges.

procedure

1. Noji cleaning
   Cleans sand, nail debris and old roofing residue. Remove dust in the order of broom → blower → wet wipe.
2. Substrate marking
   The rafter core is removed with a choke line (which will later ensure that the temporary slat is fixed).
3. Roofing (starting from sideways, starting from underwater)
   • The stacking fee for the bottom edge of the water is approx. 150-200mm. Laying horizontally is 100mm or more (150mm or more if the slope is gentle).
   • The fitting is a slanted. Crimp with a roller. The edges are reinforced with butyl tape (the shape is difficult to reverse water even if rain comes).
4. Temporary details on the penetration, valleys and walls
   • Pipe: Create a butyl "face seal" around the circumference, and then water back (diagonally rising tape) on the upstream side.
   • Tani: Lay out a temporary sheet metal (a flat plate folded in a U-shape) and seal both ends with butyl from above the roofing.
   • Wall: Do not remove the sheet metal plate yet, or replace it temporarily. Raise the roofing 100 to 150 mm from the wall and secure it with airtight tape.
5. Finished blue sheet
   Secondary protection is provided with a sheet from above to prevent UV rays and gusts of wind. The fixation is in accordance with Pattern 1.

Important notes

• If the product resumes the next day, if mud or pollen is applied to the surface of the adhesive roofing, it will cause poor adhesion during the next process. Wipe dry first thing in the morning before continuing.
• "Exposure ◯ day" is often a guideline assuming clear skies, so if there are signs of prolonged rain or a typhoon, go to "Pattern 4".

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Pattern 3: "Complete underwater" every day using "strip method (all streets)" for a few days to a week

This is a method of dividing the roof surface into a "stree-directional stripe" and completing the "underwater to above water" in one day. I imagine the number of completed belts increases each day. Even if rain comes, we will assemble the unfinished belt so that water flows.

Key points of the procedure

1. Morning: Create a "temporary drainage line" on both sides of the belt to be installed today.
   To let water escape to the uninstalled side, make a step with butyl tape to prevent reverse water from occurring at the boundary of the belt.
2. Inside the obi, go to the "eaves → building order" and then place the ground in the area → adhesive roofing main piece → temporary sheet metal by part
3. Ends on the edges of the kerabas and valleys in the order of overlapping "overlaying the unfinished side."
4. Evening: Wrap the entire obi in a blue tarp and make sure to win the upper class at the boundary.

merit

• The fittings for each part are completed every day, so there is a small risk of leakage at night.
• The flow of the scaffolding is also stable (the hands are adjusted every day with the same width).

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Pattern 4: When typhoons or front lines, you can even complete "full adhesive + temporary drainer hardware."

If the wind pressure is strong, the seat will become unreliable. Even if it's only for a short time, it's safe to have waterproofing on the surface and waterproofing on the ends.

The main points of the procedure

1. While minimizing the area where the existing slate is removed, as soon as you release the field, apply a sticky roofing main piece (at least one layer on the entire surface).
2. Eve: Apply a temporary "Eve drainer" with a galva and secure it at 200mm pitch with EPDM washer screws at the rafters.
3. Keraba: Cover the temporary Keraba cap (L bent sheet metal) and press the butyl from above.
4. Building: A cape is made from temporary wing sheet metal (even if you can just add a mountain to a flat plate), and stack the inflow side to make it a better match.
5. Tani: Temporary tani sheet metal (although it can be reused as a main unit) is laid out, and both sides are made of tape and pressed slats.

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Details on the material level and part

The eaves (the most water gathers)

• The golden rule is to bring the hem out. Turn it to the back of the fascia to flow backwards.
• The end of the roofing is inserted inside the eaves hardware before folding it back and treated with butyl.
• If the existing gutters are clogged, everything will collapse, so clean it on the first day of work.

Ceraba (the wind is peeling off strongly)

• The side edge of the sheet is pressed down with a "bath + washer screw" and the eyelets are auxiliary.
• The roofing edge is held down at least 100mm on the side and pressed with airtight tape.
• To connect with the exterior wall, raise the roof at least 100mm toward the exterior wall and then temporarily return the existing rain shutter.

Building (confluence of rainwater)

• Remove the existing building sheet metal → Remove the pierced board → Tape the nail hole to provide a point seal.
• Roofing is carried out on the ridge using a "covering method" (starting one side first, then straddling the other side from above, overlapping by at least 100mm).
• The temporary wing sheet metal can be made of flat plates folded into a horn. The stacking fee is over 150mm, and the seams are made of butyl.

Valley (most important)

• I won't open the valley first. If you absolutely need to open it, make a "face seal" with "temporary valley sheet metal + left and right roofing inserts + both edge butyl" on the same day.
• Immediately clean iron powder and sand on the valley board (causing needle holes).

Wall joints (lower buildings, bay windows, etc.)

• Start the roofing up to 100-150mm on the wall → The corner is "Folded" (cut out and folded) → Press the terminal with airtight tape.
• The existing rain cover sheet metal has been temporarily restored. Even if the final product is to be finished with new sheet metal, always return it to drain the water in the middle.

Penetration part (hood/piping)

• First, try making a prototype of the water flow using a pattern (paper tape) → In the actual product, stick butyl diagonally upwards. We are committed to making sure that "the upper class wins" is a strong sense of "making the upper class wins."
• The round hole is surrounded by double-sided butyl, and surface sealing is added to the surface. Adding tape that can become a "dripping wall" upstream will prevent it from flowing backwards.

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Work order (on a single nail level)

1. First morning: Check the weather and calculate the withdrawal time (set the withdrawal start limit at 3:30pm or 4:00pm).
2. Scaffold inspection → Installing the harness and parent rope (the height of the parent rope is above the waist, sagging control).
3. All existing snow fittings have been removed first (to damage the seats and roofing). The holes that were removed are point sealed with tape.
4. If you remove the sheet metal in the order of "building → keraba → eaves", the image of a rainy road is less likely to be distorted (doesn't touch the valley if possible until the end).
5. The slate removal area is minimized and the slate is checked for protrusion and decay of the slate nails. Remove or hammer dangerous nails.
6. Cleaning the ground → Roofing (for pattern 2/3/4) → Butyl/temporary sheet metal → Blue sheet (for pattern 1, immediately go to the sheet).
7. Evening: Re-inspect all eyelets, pedestals, and screws for looseness. Check the whole round to see if Edge is "upper win."
8. Indoor curing before nighttime rain (if the ceiling is exposed, double it with poly sheeting).

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"Numbers" for wind load and fixed

• The wind speed is q≈0.24kN/m² (approx. 24kgf/m²). The 1.8 x 3.6m seat surface is equivalent to approximately 155kgf.
• The eyelet spacing is 90cm, and when received at four points at the edges, it has a force of over 40kgf per point. Looking at the safety factor, "only eyelets" is dangerous.
• Therefore, "holding it with a surface" is based on bars (30 x 40 x sheet width) + washer screws (300mm pitch).
• Always use the screws to rafters (45 x 105, etc.). It's easy to get out by simply hitting a short screw at 12mm of the ground. The trick is to pick up the core when finding a base.

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"Numbers" for the amount of overlapping fee

• Gradient 3/10 or more: 100mm or more horizontal stacking, 150mm or more vertical stacking (fitting)
• Gradient less than 3/10: 150mm or more horizontal stacking, 200mm or more vertical stacking.
• The edges such as valleys, buildings, and crenata are added to +50 to 100mm.
  (This is an estimate that follows the "general examples" of many roofing construction guidelines. Please follow the product installation instructions for the implementation work.

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Weather judgment and withdrawal criteria

• Prediction probability of 40%, 10mm/h or more is predicted: "Pattern 2" or more is adopted.
• Gust-wind warning and approaching typhoon: Go to "Pattern 4". Prioritize waterproofing of the surface without widening the uninstalled opening.
• 90 minutes before sunset: Stopped the new opening and switched to the final check to prevent the rain from closing.
• Morning dew and radiant cooling make it difficult to get adhesive roofing on wet fields → No gas burners are used, but wipe them dry, adjust the time, and use a temporary sheet to avoid this.

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Common failures and recovery

• "Water accumulates in the valley of the sheet" → Change the position of the stove and guide the water to the eaves. It is also effective to create a ridge in the center and drop it to the left and right.
• Switch to "Fracture eyelets" → Fixing surface. For torn areas, use repair tape and board attachment.
• "The butyl is dirty and does not adhere" → Lightly wipe the surface with alcohol, then dry and re-press it with a crimp roller.
• "It bleeds through the valley" → Remove both edges of the temporary valley sheet metal and clean it → Use new butyl to seal the surface → increase the amount of engulfing.

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Example of standard flow for a day (model plan)

1. 08:00 Scaffolding, safety belts, and parent rope confirmation, tools development
2. 08:30 All snow stoppers removed → nail hole point sticker
3. 09:30 Remove the kerabas sheet metal and ridge sheet metal (does not touch the valley)
4. 10:30 Turn the existing slate to the minimum necessary → Clean the Noji
5. 11:00 Adhesive roofing temporary laying (today's obi only)
6. 12:00 Lunch: Simple curing with blue tarp (wind prevention)
7. 13:00 Temporary details of the walls, penetrations and valleys (butyl + temporary sheet metal)
8. 15:30 End judgment → Main blue sheet protection + check the entire round
9. 16:00 Clean up → Rain gutter inspection → Indoor curing

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"Dimensions and tools" that support construction

• Underground finder: Measure the position of the rafter core from the attic with a tape measure and transfer the dimensions to the roof. The screws work when you spot patterns such as the main purse spacing of 910mm and the rafters 303mm.
• Folding the edge of the sheet: Diffracts twice to make the thickness slower the eyelets.
• "One sheet can't cover a large area": ​​The larger the wind support surface, the more dangerous it is. It is safer to divide 3.6 x 5.4m into two pieces and stack them in the flow direction.
• Storage of butyl: Keep it warm in the shade in the summer and indoors in the winter to make it the best adhesive.

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Approximate material quantity (estimate)

• One side of the roof 6m (eave) x 5m (flow length) = 30m²
  • Adhesive roofing (1m wide x 20m/roll): Approximately 2 rolls (estimated effective 17-18m²/roll if stacked)
  • Blue sheet: 2-3 3.6 x 5.4m sheets (assuming that stacking them to create a step)
  • Bath: 3 5m x 3 burrs in the flow direction, and keraba, building and eaves are added to add a total of 20-25m
  • Washer screws: 200-300 (300mm pitch x total extension)
  • Butyl tape: 2-3 rolls of 50mm wide x 10m

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Minimum laws and etiquette (Japan)

• Wear protective equipment when working at high altitudes and prevent shattering in the vicinity (fire-retardant mesh sheets and tools fall).
• Waste materials and nails are collected every day. Prevents leakage into the gutters and the premises.
• Slate, which may be asbestos, does not cut or crush it on your own judgment. Follow the instructions of the local government and enter the registered company.

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Tips for returning to the finishing process

• If there is mud or dust on the adhesive roofing, the finishing material is less likely to adhere to the adhesive material → wet rag → wipe dry → reset by roller crimping.
• Always point seal holes with tape before removing the temporary sash and screws.
• Temporary sheet metal on the valley and walls can be reused to the main unit if the dimensions are correct. Replace if there are scratches or bends.

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Summary

"Closing the rain along the way" seems to be a difficult task, but in fact it all comes down to three things: "continuous rainy roads," "up and hierarchical relationships," and "fixing the surface to the wind."
For a short period of time, use "sheets + timbers", for overnight roofing, use "surface waterproofing with adhesive roofing", for several days, use "strips every day", and for a typhoon, use "full adhesive roofing + temporary drainage".
If you keep a numerical guideline (wind pressure and stacking fee) on hand and finish it with the same mold every day, you can achieve a stable "roof renovation that won't get wet" even when using DIY.

If you're wondering "How much renovation or remodeling can I actually do on my own home?" or "Where should I even start?", please visit this page. If you're looking to learn more about specific renovation processes or construction details, don't miss this page as well!

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Reference materials/reading materials/videos (as support for practical work)

(The specific product specifications and numbers in this article are based on the "special examples" of general construction guidelines. For actual work, please be sure to follow the construction manual for the products used and guidelines of each local government.)

• Architectural Institute of Japan "Building Load Guidelines and Explanation (Wind Load)": Background of the concept of velocity pressure q≈0.6V² (professional).
• Japan Housing Finance Agency's "Wooden Housing Construction Specifications": A general example of stacking widths and fittings for roof undercover materials.
• Installation instructions for major roofing manufacturers (reformed asphalt, adhesive, high heat-resistant type exposure allowance, etc.).
• Japan Meteorological Agency "Past Weather Data Search": Useful for understanding the approximate rainfall intensity and wind speed in a region.
• On-site videos (roofing installation, fitting at valleys and walls, "correct way to lay blue tarps" etc.).
• Asbestos countermeasure page for each local government: Precautions for when identifying, handling slate.
• City rooftop Kagoshima store "Is it bad for it to rain during roof renovation? what you should be careful about”

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Very important! Rain close to prevent leaks

Appendix: Checklist (printing recommended)

• Is the "opening range" today's minimum?
• Was the snow stoppers and protrusions removed first/Has the hole been pointed?
• Is the sheet fixing method "pressurize it with a surface" (barrel + washer screw 300mm pitch)
• Are all stacking directions winning "up → down"?
• Did you create a face seal from butyl for the valleys, walls and penetrations?
• Have the gutters been cleaned/Has it been cured to prevent them from getting stuck with fallen objects?
• Did you switch to "Rain Closure Complete Mode" 90 minutes before sunset?
• Have you forgotten the secondary treatment (policy) inside the room?
• Have you seen a review of the weather and wind (gusts of wind and thunderstorms at night)?