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2 Answers

Liquid-applied flashing across dissimilar materials?

Can a liquid-applied flashing product like Zip System Liquid Flash or Prosoco Fast Flash span a gap between different building materials? The particular situation I can think of would be the application of liquid flashing to the inside surfaces of a window buck and out onto the face of exterior rigid insulation like foil faced polyiso. Seems like adhesion and flexibility could be suspect.

In General questions | Asked By Brian Coppola | Jul 11 14
10 Answers

Stem wall ledge for slab support

I'm leaning towards doing a slab on grade foundation with a stem wall for a new house, and have been thinking about slab edge insulation details. The most common approach seems to be to include a ledge, something like a brick ledge, on the interior of the stem wall. This ledge is usually wide enough to allow for up to 2" of insulation at the slab edge, while still allowing for the slab to slightly overlap it.

In General questions | Asked By Graham Fisher | Jul 10 14
2 Answers

I applied rigid form insulation to the inside surface of the existing sheetrock in a bedroom

Prior to placing the insulation, I glued heavy fabric to the front to give it an aesthetic balance with the bedroom.

My concern: Will the form board out-gas causing harm to the occupants?

In General questions | Asked By Robert Mela | Jul 11 14
1 Answer

How to improve the walls for a 1000-square-foot house near Asheville?

What would be the best way to improve the walls in a 1000-square-foot house that currently has 2x4 walls with fiberglass batt insulation covered with OSB, felt paper, and vinyl siding?

I want to replace the vinyl siding with fiber cement plank siding, and thought this would be a good time to add some XPS insulation between the OSB and the siding. The felt paper undoubtedly will be damaged by removing the vinyl siding, so I am guessing I need a house wrap (Tyvek or other) and then the XPS sheets.

In Green building techniques | Asked By Stuart Murray | Jul 10 14
1 Answer

Fixing undersized ductwork - best approach for difficult section?

I've just uncovered some ductwork in my house that needs to be addressed. It is a 1400 square foot two storey brick house, no wall insulation, in climate zone 5. It's a narrow and tall Victorian house and the ductwork in question feeds the rear of the house on both storeys - kitchen on the first floor and a bedroom on the second. These rooms have been poorly heated ever since I've lived here but last winter, which was particularly testing, the rear bedroom was basically uninhabitable without backup electric heat.

In Mechanicals | Asked By Jonathan Dalton | Jul 10 14
13 Answers

Mobile home floor plans’ fatal flaw

From a practical perspective mobile homes have a fatal flaw…no indoor storage space.

Now that awesome construction is available, it’s time to bring mobile homes into the mainstream by re-thinking space and floor plans, especially storage space requirements!

There is no space for the stuff a normal family/person needs to store. So what happens? The place starts to look like a junk heap because there is no storage space. People start to store stuff outside, maybe put up a shed…maybe they rent a storage unit…there goes the supposed savings.

In Energy efficiency and durability | Asked By Anneal G | Jul 9 14
1 Answer

Can wired floor heating cause EMF issues?

I am considering floor heating for my bathroom remodel even for my first floor kitchen and family room. I now have gas forced hot air heating.

For electrical wires under the floor, I have concerns on EMF. But for hot water pipes under the floor, then leaking is my concern.

Please advise.

In General questions | Asked By meitien hsing | Jul 10 14
21 Answers

Post your cut-and-cobble stories

I have decided to write an article on the topic of Cut-and-Cobble Insulation. Even though I sometimes scoff at the technique, calling it an unprofessional method beloved by homeowners, I must admit that I have used cut-and-cobble myself. Sometimes, the method makes sense.

For those who don't know, the term refers to the insertion of strips of rigid foam between studs or rafters. Each rectangle of rigid foam is sealed at its perimeter with caulk or canned spray foam.

So I'm asking for help.

In Energy efficiency and durability | Asked By Martin Holladay | Nov 13 13
2 Answers

Foil-faced polyiso left exposed longterm - impact to R-Value?

A client's deep energy retrofit got started but stopped about 16 months ago, right after the foil-faced polyiso was installed but before the siding was installed. All polyiso joints and almost all edges were taped and sealed. The tape looks great (pretty amazing after two very hard zone 5 winters).

In Energy efficiency and durability | Asked By Kristen Simmons | Jun 25 14
4 Answers

Why spend so much (any) effort insulating the building slab?

I have just enjoyed reading 2-3 years’ worth of blog posts on the site and (Living in Australia) I am intrigued by how much effort and resources (foam) is used to insulate a home’s slab/basement from the ground in some of the high performance builds.

Surely doing this just introduces complexity and opportunity for movement of the slab? Should houses even have basements anymore? They seem like they make it much harder to insulate your building envelope. The only advantage would seem to be if you wanted to utilise the thermal mass of the slab.

In Green building techniques | Asked By David Hall | Jul 2 14
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