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14 Answers

can you create a blog on infrared heating panels?

People would benefit from knowing how infrared heating panels are more efficient, comfortable, and safer than conventional heating methods.

Asked By Iona Jonasson | Oct 19 16
5 Answers

Double backdraft damper needed for bathroom fan?

I am going to install Panasonic exhaust fans in our bathrooms in new construction through an unvented attic.. The Panasonic fan comes with a built-in damper and their installation guides mention using a wall cap with a damper too. This means there are two dampers.

The Panasonic damper is very light plastic does not seal well and opens easily. The wall cap damper is typically metal, making it a little harder to open. Our HVAC contractor suggests not using a damper at the wall cap but this worries me.

Is the best approach to use two dampers in line?

Thanks for your advice.

Asked By Jeremy Turner | Oct 19 16
2 Answers

Taped Zipwall or sheathing with Ice & Water Shield on a REMOTE/PERSIST roof?

So any thoughts on what is better or more practical?

I'm getting ready to start sheathing a roof (which will have all of it's insulation outboard of the WRB and sheathing, with a cold roof on top). It is a R-66 EPS roof.

On one part of the project (a separate building, same construction technique (REMOTE/PERSIST), we used barnboard, then 1/4" plywood (to hide the ice & water shield above it) from showing through any knots or such from below (exposed cathedral ceiling), then R-66 of EPS above, with 2x4 furring and then plywood and then metal roof.

Asked By Brad Hardie | Oct 20 16
5 Answers

Insulating over cedar siding with 1-inch rigid foam underneath

Hi All, Just purchased a home in northern Michigan. Built in 1988 with 1" of TUFF R(?) foam under vertically applied cedar 3" T&G. After inspection there are 2x4 stud walls, 3 1/2" fiberglass insulation,plywood sheathing, 1" TUFF R foam, 5/4 cedar siding, and no drainage opening. I was trying to add insulation to the exterior. Thinking about ROXUL board directly over the cedar, furring strips, and different siding. Any thoughts on this plan.

Asked By Bill Skaff | Oct 17 16
4 Answers

Garage and root cellar insulation

I received a call from my mechanical engineer today asking me how I planned to insulate the garage and root cellar ceilings. Both rooms are in the basement and above those ceilings are first floor living spaces. I told him my plan is to dense pack them with cellulose and probably add an inch of Polyiso covered with a layer of gypsum to break the thermal bridge and satisfy fire code. I was planning on insulating the rim joists with a couple of inches of ccSF on the inside, the only area in the house with the nasty stuff, mineral wool on the outside, and then dense pack would fill the bays.

Asked By Jonathan Lawrence CZ 4A New Jersey | Oct 19 16
10 Answers

Unventilated, highly insulated roof — replacing shingles

We are replacing the shingles on a cathedral roof.

The roof has been insulated from the inside. 8 inches of expanded polystyrene below the roof deck including cut and cobble between the rafters, and 4+ inches of additional eps and mineral wool below that.

The roof is not ventilated.

The shingles will be asphalt.

From what I have read, asphalt shingle roofs are not water or vapor permeable, so using a permeable underlayment will not provide a benefit, because vapor will still not be able to dry through the shingles.

Two questions.

Asked By Sharon Secrist | Oct 20 16
17 Answers

Mitigating high indoor humidity

I've been battling indoor humidity issues for some time now and need more advice.

Here are some quick stats:

--Location: Western Washington

--1600 sq ft one story rambler built in 1987

--Two adult occupants and two indoor cats

--Main heating is supplied by a free standing propane stove that vents to the outside. Supplemental cadet wall heaters

Asked By Travis Canfield | Oct 18 16
3 Answers

What's the best all around roofing/insulation solution for Zone 5?

Hello to the community. I am in northern Nevada zone 5. This is an arid valley with normally low humidity but it can get some really high winds... upwards of 80 mph. The house I just bought was built in the 70's. There is about 6 inches of blown insulation in the attic but none under the roof sheathing. I do plan on bringing the attic insulation up to at least R40. The attic has two small gable vents but zero soffit vents. The roof is completely failed cedar shakes with a lot of exposed sheathing throughout.

Asked By Roger Smith | Oct 20 16
9 Answers

What's the best way to renovate/rebuild an old south-facing exterior wall?

Hi All - I am a newbie to this group but have considerable building experience remodeling and renovating homes, and completing unfinished properties. Still, I am no expert building contractor.

Asked By Roger Smith | Oct 2 16
2 Answers

2016 heat-pump water heater rebates - Opinions on best heaters?


There is a $750 Massachusetts rebate on air source water heaters. There are a lot too choose from. Any opinion on which one would be the best choice for a small 2 bathroom?

Thanks for any input.


Asked By Seth Capista | Oct 18 16
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