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2 Answers

Insulating Rim Joist Beyond Foundation?

Situation:
Completely below grade basement in Zone 5.
Poured concrete foundation
Water barrier/proofing sprayed on foundation.
R-5 rigid foam applied to foundation (on top of water barrier)
Rim joist insulated with roughly r-7 rigid foam foil faced on both sides. Over the insulation (interior side) is a 1/2" piece of OSB. The floor joists butt into this OSB. The joints of the OSB were caulked.

Asked By BobTheWeekendWarrior | Dec 11 17
7 Answers

How to tell if I need a HRV?

So at the conclusion of my home energy audit, it was recommended that a heat recovery ventilator be installed because my house (built in 2002) is already too tight.

I always though excessive wintertime moisture was a good indication that a HRV was needed. However, the humidity level in my home drops to about 17% in the dead of winter. Isn't this an indication that I already have a ton of air infiltration?

I'm very confused and wonder if the auditor performed the blower door test incorrectly. Could the forced air system be the culprit for the dry air?

Thanks in advance!

Asked By BuildingNewb | Dec 10 17
6 Answers

I would like opinions on my basement insulation plan

Hello all,

I plan to insulate and sort of half finish my concrete basement for use as a woodworking shop and playroom. Despite a perimeter drain and good gutters, grading etc., there is an occasional damp spot along the edge of the floor during heavy rains, but it is mostly dry.

The goal: to make the basement cozy (it's cold; I'm in Massachusetts) and avoid the telltale musty smell of the thoughtlessly finished basement. I'm a somewhat ambitious DIYer, but I am not 100 percent confident in my scheme and would appreciate feedback, especially from Martin et al.

Asked By Alexander Lane | Dec 10 17
16 Answers

New construction: surface-mount LEDs in J-boxes or cans with retrofit modules?

I have to install 100 ceiling mount light fixtures in a new house. My electrician suggested that I consider changing from cans with LED retrofit modules to 4" junction boxes with "surface mount" LED fixtures.

This appears to be a new enough phenomenon that I am having difficulty assessing the pros and cons of these two options. Your thoughts are much appreciated.

Insulation will have some sprayfoam sections and some fiberglass.

Examples of LED fixtures that work with a J-Box:

http://www.nuvolighting.com/s9190.html

Asked By Bradley Lepkowski | Feb 28 16
6 Answers

Zip System vs. OSB

I am in the process of choosing between zip system and osb sheathing for the exterior of a new home project. I have read through a lot of articles on this site though I am still trying to decide on if it is worth the added cost if OSB is installed cautiously. I would still use a high quality tape on all seams. I intend to use a high quality sealant inside at the plates and blocking to sheathing joints. I also intend to install Tyvek on the exterior since the home will have vinyl siding and I don't want to rely on the tape alone at sheathing joints (if using zip).

Asked By Brian Ducharme | Dec 10 17
4 Answers

Mini split head blowing cool air

I have 4 half ton heads and a 1.5 ton head in my house that were recently just commissioned. One head seems to blow considerably cooler air than the rest. I have checked almost 100% of the lineset into the unit from the branch box and we no kinks. The branch box does recognize I have 5 heads hooked up. It did seem like it was blowing a bit warmer when it was the o my head running.

Any ideas? Thanks in advance.

Asked By Mike M | Nov 26 17
7 Answers

Repair or replace sheathing behind brick veneer

I wanted to get some advice on what to do with existing sheathing material that is currently installed behind brick veneer in a 1980's home I'm currently renovating. It's located in Houston, is 2x4 wood frame construction on concrete slab foundation, and the other parts of the house have T1-11 and vinyl siding (which will all be eventually replaced), but my questions concern what to do behind the brick for now. Much of the interior has been gutted down to the studs due to issues with mold and pests.

Asked By sdcnyhou | Dec 8 17
4 Answers

Brick house insulation

Hello,

My situation: I have a brick house, that initially had plaster and lathe walls. With the floor joists supported by inner wythe, and the joist ends embedded in the brick. I removed the plaster and restudded the walls with 2x4s.

My concern: On the lower floor, I insulated the stud bays with batt insulation. I thought this was a good thing, however, after reading your article I think I may have been mistaken.  I am beginning work on the second story and don't want to make matters worse.

Asked By 3rd Little Pig | Dec 9 17
9 Answers

Building a furnace room in the attic

What is the best way to build a furnace room in the attic?

How big should the framing be? 2x6s? Also, should I attach plywood to the framing or just nail polyisoprene directly to framing? How many layers of R13 Polyiso? Is it better to do 1 layer of foil faced polyisoprene on the inside of the framing and then just put fiberglass batts on the outside?

Thanks a lot?

Asked By BuildingNewb | Dec 6 17
1 Answer

Does traditional plaster serve as a sufficient air seal between living space and attic in an older home?

We're restoring an older balloon-frame structure (1890s) in a northern Gulf Coast climate (extreme humidity, some heating load, large cooling load). Fortunately, we've been able to design the house's first ever HVAC system so that all the ductwork and mechanicals are located in a fairly short run down the long central hall -- within the conditioned space, and just beneath the existing ceiling plane (a false drywall ceiling will sit a foot or so below the old ceiling). The existing ceiling over most of the house is a rather thick plaster (with surprisingly few visible cracks).

Asked By user-6970120 | Dec 9 17
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