DIY Builds
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How do you insulate a shed roof on a house?

The simplest is one you suggested: Fill the rafter cavity with successive layers of extruded polystyrene (XPS) that also will stop air movement and act as a vapor retarder. Be sure to seal each piece of insulation (at all sides) to the framing and to seal any penetrations (wiring, vent pipe, etc.)

What wood should you not cook with?
What wood should you not cook with?

Type of Wood Softwoods such as pine, redwood, fir, cedar and cypress are not ideal for cooking because they contain terpenes and sap. This gives...

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How do you know what drill bit to use for an anchor?
How do you know what drill bit to use for an anchor?

The diameter of the hole you drill should be slightly smaller than the diameter of the screw. So, for example, if you're using a 3.5 mm screw, use...

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Are shed plans easy to follow?
Are shed plans easy to follow?

These are! They guide you every step of the way to complete your dream shed.

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Q:

I’m planning a small shed-roofed addition that will tie into my house’s gable roof just above the eave. The rafter tails will be exposed with no soffit. I’m considering a flat ceiling, with insulation batts between the ceiling joists and a vapor barrier. Would it be better to insulate between the rafters with extruded polystyrene? What about ventilation?

Tim Olsen, SD

A:

Bruce Harley, an engineer and the author of Build Like a Pro: Insulate and Weatherize , replies: Venting a shed roof is a tricky proposition, and its necessity is debatable in a cold climate like yours. But there are a couple of effective options for unvented cathedral ceilings. The simplest is one you suggested: Fill the rafter cavity with successive layers of extruded polystyrene (XPS) that also will stop air movement and act as a vapor retarder. Be sure to seal each piece of insulation (at all sides) to the framing and to seal any penetrations (wiring, vent pipe, etc.) with canned spray foam or caulk. Pay extra attention to sealing the XPS to the top plate of the new and old eave walls. With a small job, it won’t drive you nuts to be a detail fanatic. That’s the short answer, but I see a red flag where the low-slope roof meets the steep roof: It’s an ice dam begging to happen. In terms of heat loss, your house is probably leakier than your addition will be, and the heat loss may melt snow that will run down and refreeze when it hits the new roof. When shingling the new roof, strip off 3 ft. of shingles above where the roofs meet, and install peel-and-stick rubberized roofing membrane on both the new and old roofs. This will help to prevent the effects of ice dams, but insulating and sealing the existing attic can help to prevent the actual ice dams.

From Fine Homebuilding #169

Can you use pallets as firewood?
Can you use pallets as firewood?

As firewood You can burn heat treated pallets safely since they have not been chemically treated. Apr 3, 2019

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Is MDF better than particle board?
Is MDF better than particle board?

MDF is fairly stronger than particle-board. Particle-board is not very strong. MDF is quite durable. Particle-boards are relatively less durable....

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Does lemon water help plants grow?
Does lemon water help plants grow?

Lemon juice won't nourish plants, at least not heavily. It will only harm them over time. Only use lemon juice if you intend to show acid rain...

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What can I use instead of a joist hanger?
What can I use instead of a joist hanger?

The most common alternative to using joist hangers is a ledger strip. This technique requires a plank of wood to be secured to the outside wall and...

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What can I make with 2 wood pallets?
What can I make with 2 wood pallets?

15 Creative Uses For Wood Pallets Standing Garden. Because of the space between each slat, these are easy to pack plants into to make a very...

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Are shed plans easy to follow?
Are shed plans easy to follow?

These are! They guide you every step of the way to complete your dream shed.

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Does foil bubble wrap insulation work?
Does foil bubble wrap insulation work?

The R-value of foil-faced bubble wrap is so low that it has few, if any, advantages over rigid foam. Of course, the product's foil facing can be...

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