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1 Answer

One or two HRVs?

I recently purchased a ~3000 sq. ft 2 story colonial built circa 2001 in the seacoast New Hampshire area.

It has an unfinished/unconditioned basement. It has a unfinished walk up full height attic, with only the front roof requiring a knee wall.

I plan on converting the attic to conditioned living space. That will add ~5-600 additional sq. ft.

The house has hydronic baseboards. There is no A/C nor HRV ductwork.

Asked By Matt Zahorik | Nov 28 12
3 Answers

How to mount a deck ledger on a Larsen truss wall?

We need to mount a 2x8 pressure-treated deck ledger to a conventionally framed wall that has a 8" larsen truss attached to it.

The frame is as such: 2x10 rim joist bearing upon 2x6 mudsill, 5/8" T&G OSB, 8" Larsen truss, 1x4 cross-strap, Tyvek. The deck ledger will be mounted at the same elevation as the rim joist.

The supported length of the deck is not too great, between 5-8'. I would like to attach the ledger on the same plane as th 1x4 strapping and not directly against the OSB.

Asked By erik olofsson | Nov 27 12
5 Answers

Can I put foam board insulation on top of one floor and lay another floor on top of it?

I have a enclosed porch that I am trying not to crawl under to put insulation. I also want to make the floor level. So I want to know if I put foam board insulation on top of the old floor and level the new floor, will the new floor keep the cold out?

Asked By Greg Logan | Nov 25 12
7 Answers

Vented Roof Cavity?

For annoying reasons (drawings were wrong, framer didn't catch in time), the roof on an addition we're doing was built lower than it needed to be to line up with the soffits on the existing house. We decided the easiest solution would be to just build up a 6" frame on top of the sheathed roofing so that the new higher roof would line up correctly. The original roof is still in place and has 6" of open cell foam on the underside. The result is that we have a roughly 6" dead space between the foamed, sheathed and papered original roof and the new sheathing. We're putting a metal roof on.

Asked By Mike Ball | Nov 28 12
1 Answer

Insulating under a hydronic radiant heat under subfloor between joists system

I have hydronic radiant heat set up attached to the underside of subfloor and between floor joists spaced at 16". This set up sits above 1400 sq.ft. of unheated basement and needs to be re-insulated. Above it is the traditional subfloor with 3/4" engineered oak flooring immediately on top. I have been told many different methods to insulate this ranging from reflective bubble foil to standard fiberglass batting with a face to rigid insulation to any combination of 2 or more of these.

Asked By Doug Adler | Nov 28 12
1 Answer

Soffit vent - leave or remove?

I am going to be converting my vented attic to a sealed & insulated attic. We'll be applying spray foam to the underside of the roof deck between the 2x12 rafters, and at the gable ends. It's a simple gable roof, 8:12 pitch. It has a substantial overhang past the exterior wall, with angled fascia and angled soffit panels (i.e. the soffit panels are nailed directly to the underside of the rafter tails, at an 8:12 pitch)

Asked By Michael Hansen | Nov 28 12
3 Answers

Too many vapor barriers with a cold (unvented) roof retrofit?

I'd like to retrofit our existing ventilated roof to an unvented (cold) roof per Martin Holiday's musing "How to Build and Insulated Cathedral Ceiling" (http://www.greenbuildingadvisor.com/blogs/dept/musings/how-build-insulat...) and various Building Science articles but specifically the one included in Fine Homebuilding recently. (http://www.buildingscience.com/documents/published-articles/pa-crash-cou...) In the Building Science article Joe Lstiburek provides details on how an unvented roof can be built by insulating above and below the roof.

Asked By Andrew Alden | Nov 27 12
7 Answers

Can I make interior thermal shutters for my windows?

I have single pane windows and would like to insulate them. I was thinking I could put some rigid insulation over them as a shutter and then hinge it at the top. I could lift them in the day and hook them to the ceiling and lower them at night. This would provide added value because it would really block out the light at night, provide sound insulation, and will double as a place to pin drawings that the kids make. When I went to buy this rigid insulation, I read a flammability advisory for R Max. Then I checked a piece at home, and yes, it does burn.

Asked By PETER SCHWARTZ | Nov 10 12
20 Answers

Heat Transfer Plates for Radiant heat under floor joists

While everyone can agree on certain aspects of radiant heat systems e.g., most of the time PEX tubing is the right choice, there is a lot of divergence of opinion on the use of aluminum heat transfer plates in under joist installations over untreated living space. The closest I've been able to come to a reliable answer is a study done that seems to suggest that they are a good idea (ASHRAE Research Project 1036 "Develop Simplified Methodology to Determine Heat Transfer Design Impacts Associated with Common Installation Alternatives for Radiant Conduit")

Asked By Michael schlee | Jan 4 12
5 Answers

Geothermal or AirSource Heat Pump

I'm trying to make a decision on which type unit to go with. House is approximately 1665 sq foot ranch with equivalent walkout (daylight basement). See plan here: http://houseplans.co/house-plans/1236/

Asked By Aron Robinson | Nov 24 12
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