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4 Answers

Mini split duct problem


I am adding two new rooms onto my house; one room is a 13x26 with one octagon window and the other is 7x10 with no windows. The two rooms are located next to each other and would be considered "renovated attic space".

I had 3 HVAC bids provided and the cheapest one was over $5,500 so I decided to DIY the project.

In Mechanicals | Asked By M C | Sep 20 16
4 Answers

Insulation below rat slab

Given the usual requirement to put insulation beneath a concrete basement floor, why isn't it useful to place underneath a rat slab (2 inch concrete slab) in a crawlspace? Is it a matter of payback?

thanks, Sacie

In GBA Pro help | Asked By Sacie Lambertson | Sep 19 16
8 Answers

Vented over roof on parallel chord truss

I'm about to commence a project and I've got all the details dialed in up to the roof and I'm leaning towards the following.

In Green building techniques | Asked By Will Schebaum | Sep 19 16
10 Answers

Strapping for dense-packed cellulose

Looking for recommendations on the correct strapping spacing (12" or 16") to help prevent bulging with a dense pack cellulose installation on walls. We will be using Insulweb over 8" cavities, 16" on center framing.

In GBA Pro help | Asked By Jessie Pratt | Feb 25 14
5 Answers

Permeance and latex paint

Martin et al.,

I have a question for a "Pro" on this blog. I am looking into different encapsulants or paints to go over lead paint in an older home remodel. The permeance for these latex based encapsulants varies widely.

In GBA Pro help | Asked By Michael Enos | Sep 19 16
15 Answers

Attic insulation

We have just built an addition to our house. It is two floors and a basement. The 1st floor is a kitchen and is open to the existing house. The second floor is a master bedroom and a bath. The only connection with the existing house is a door. There is an attic space above the bedroom/bath. It is an engineered truss roof so the space is not usable. We have sprayed the underside and ends with closed cell foam. to R38 or better. The only penetrations into the roof cavity are 1) the bathroom fan,which vents out of the gable end and 2) a required panel in the closet for access to the roof cavity.

In General questions | Asked By Joe Strauss | Sep 16 16
4 Answers

Insulation for retrofit and thermal bridging questions

Hello all,

First time posting and I am hopeful that I can convey my questions accurately. I recently purchased a 1997 home in NC and found out this summer that our home insulation is horrific. One primary reason is design. We have a two car garage (west facing) with a bonus room overhead which are located on the opposite end of the home from our HVAC units. The left, back, and front wall of the garage are open 2x4 stud unfinished. The garage door is uninsulated. The garage's ceiling and common wall to the living space is finished.

In General questions | Asked By Brian Williams | Sep 19 16
3 Answers

Basement insulation with different slab levels

My proposed basement has 2 levels and I am trying to finalize the details to insulate where the 2 levels meet. I am planning on insulating the perimeter walls from the inside. However, where the floor levels change I am contemplating insulating under and around the footer, and then up the sides of the foundation wall to the top of each slab. The assembly from top down is 4" concrete, vapor barrier (not shown), 4" of EPS type IX, 4" of 1/2" clean stone, undisturbed earth. The footer is 30" wide x 12" and the foundation wall is 12" wide, standard size around here.

In Plans Review | Asked By Jonathan Lawrence | Sep 18 16
4 Answers

My interior fireplace tile chipped over a year ago

My interior fireplace tile chipped over a year ago. Now a powdery efflorescence has eaten away at it. Four tiles are now eaten up, flying off, deteriorating before my eyes. Our 1927 fireplace will flake away in a matter of time. A masonry guy inspected it.

How do I attach a picture in this Q/A?

In General questions | Asked By Gina Allen | Sep 18 16
1 Answer

How to cover exterior insulation?

I'm having a hard time figuring out how to cover the exterior foam insulation on my house. There are only a few spots showing but they show some damage already from falling branches/rain/snow. Quikrete and Tuffcoat aren't available where I live so I was thinking of using surface bonding cement?? Is this the correct option? And do I need to add something to strengthen it?

In General questions | Asked By Jenna Bond | Sep 19 16
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