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5 Answers

Workshop with dwelling above: Heating advice?


Asked By User-6964558 | Dec 12 17
4 Answers

Ductless minisplit heat pump in a poorly insulated home?

Good morning,

I’m trying to find some information on the pros and cons of Ductless mini split heat pumps. (Mostly if one could work in my situation.)

My home is a 1930’s Cape Cod style home (Climate zone 4) with a full shed dormer on the front. The home is roughly 1100 sq feet. The first floor approx. 780 sq feet has an open floorplan that connects living/dining and kitchen with a sectioned off bathroom and guest bedroom. The 2nd floor approx. 275 sq feet serves as a master suite that has a sectioned off bedroom and bath.

Asked By Andy Pappas | Dec 13 17
3 Answers

Exterior mineral wool insulation: Batts vs. denser boards

I am planning to add exterior mineral wool insulation over the exterior of my double wythe brick walls. The typical choice is high density boards such Roxul comfortbatt 80. They are substantially more expensive than the medium density mineral wool batts that typically go into stud bays on the interior such as Roxul Comfortbatt. I think the price difference is factor 3 at least on a $ per R per sqf basis. Hence my idea: Attach a 2 by 4 on the flat with Tapcons to the brick.

Asked By Matthias Paustian | Dec 12 17
6 Answers

Insulate "crawlspace"

I put crawlspace in quotes because this is more of an unfinished basement with dirt floor. The joists above range from 7-10' above grade. The floor slopes 5' in the middle. I currently have no plans to finish the basement.

The house is in Zone 6. I want to make it more cost effective for heating and keep the moisture controlled.

My plan is as follows:
1. put 15-20 mil plastic over the current plastic sheets which has been walked on and is now covered in holes. Re-attach to foundation and seal using tape.

Asked By James Bodell | Dec 11 17
6 Answers

Exterior foam with stone and 10 mm rainscreen

I am planning to build a new house and I have a couple of questions.

The house will be in climate zone 2 - hot-humid (near Houston, TX). The walls will be 2x6 with 3.5" of open cell spray foam. The walls will be sheathed with OSB and we are planning to add 0.75" of foam board (R4) on the exterior and use Tyvek drainwrap and a 10 mm rainscreen (i.e. MTI Surecavity).

Some of the walls will have a full stone veneer (3"-5" bed). Some will be half stone and half Hardie and some will be all Hardie. My questions are:

Asked By E247 | Dec 5 17
0 Answers

Direct source for IGUs?

A few years back we built some custom sliders for my house and somehow I got Cardinal to sell directly to me. I own a business with a loading dock and a Federal tax number, and was buying a fair bit of glass. I called some time later and the sales guy had retired and the phone plebe gave me some numbers to call that were wholly inappropriate, a replacement window company etc.

In my experience your basic local glass company has expertise that ends with loE and argon, start asking about specific coatings and performance and you are wasting your time

Asked By Keith Gustafson | Dec 11 17
1 Answer

Should I use drywall or OSB as the air barrier?

Zone 5 in Maine. Stackup is: vertical siding, Hydrogap, OSB, 2x6 with Roxul.

Question is: Should I use drywall or OSB as air barrier in between 2x6 wall and the 2 inch utility chase which will also be insulated?

If drywall, should it be paperless/ fiberglass?

Looking for experiences including Joe L's method.

Asked By JeffNMaine | Dec 12 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:

Asked By Bradley Lepkowski | Feb 28 16
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
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