Why are vapor barriers bad?

Vapor barriers are supposed to stop vapor diffusion through roofs, walls, and floors. But they can also can trap moisture, causing rot and mold. Where moisture comes from: Water vapor can be forced into wall assemblies from the warm side of the house.

greenbuildingadvisor.com - Vapor Barriers Are a Good Thing, Right? - GreenBuildingAdvisor

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A good rule of thumb is to put a maximum of 16 outlets on a 30 amp circuit.

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How do you waterproof a shed indoors?

At a glance: Start with your shed base – get it right before you build your shed. Apply regular timber treatment to prevent rot. Inspect weak...

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At the dawn of our current interest in building science, sheets of polyethylene were routinely stapled to interior framing before drywall was installed. The idea was to block the flow of water vapor into exterior walls. (Some builders tried to make their polyethylene seams airtight, so that the poly would do double duty — acting as an air barrier as well as a vapor barrier.) Installing a vapor barrier (or more properly a vapor retarder) was considered cutting-edge. But in time, builders began to see flaws in their approach. For one thing, it was virtually impossible not to damage or puncture the barrier during installation or after it was applied. The plastic sheeting was usually full of holes by the time the house was complete. As it turns out, these holes did not affect polyethylene’s performance as a vapor retarder — a ripped, torn vapor retarder works very well. However, these holes undermined the poly’s performance as an air barrier. Since polyethylene reduces the ability of a wall to dry to the interior during the summer months, some builders began to worry the vapor barriers trapped moisture inside walls where it could do a lot of damage.

Thus began a muddying of the waters: when and where are vapor barriers a good idea?

Sandra Heiser wades into this debate with a Q&A post that’s the subject of this week’s Q&A Spotlight.

Leave the poly in, or take it out?

Heiser writes about a house near Buffalo, N.Y., that is ready for drywall. She describes the exterior wall assembly as follows: vinyl siding, 1 in. of rigid polyisocyanurate foam, 1 in. of sprayed closed-cell foam, fiberglass batts, and, finally, clear plastic. “I’m thinking [the plastic] has to go,” she writes. “What are our options? Is it… Weekly Newsletter Get building science and energy efficiency advice, plus special offers, in your inbox. Signing you up... Sign Up This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

What is a garage without walls called?

Carports. A carport is an open garage… just a roof and no walls (open sides). Jul 29, 2019

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What flower means love?

Camellia. The general meaning of these flowers is love, affection and admiration.

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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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What kind of foundation should I use for a shed?

gravel pad What is the best shed foundation? A gravel pad (crushed stone) with a lumber perimeter is the best shed foundation option in most cases. We recommend gravel shed foundations because they provide a stable base for your shed to rest on and do a great job of draining water away from the bottom of your shed.

siteprep.com - Shed Foundations: The 13 Top Options - Site Prep

Sheds have exploded in popularity over the past several decades. From being simple, DIY outbuildings, sheds have evolved to include workshops, offices, and even living space. What do all these buildings have in common? They all need some type of shed foundation to support them! Thankfully, the number of shed foundation options is beginning to catch up to the variety of sheds. Here are the 13 top shed foundations that you should consider for your outbuilding. However, if you’re not interested in reading the full list, we’ll save you some time and give you our recommendation for the best shed foundation right away.