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8 Answers

Adding mechanical ventilation to a leaky house

I have an older home that I know leaks a lot of air, and I’m wondering if adding mechanical ventilation would improve the indoor air quality.

When i first bought the house, it tested over 10 ach/50. I have since improved the basement by air sealing the rim joist, service penetrations and the slab to foundation wall cracks etc. The house was last tested around 8 ach/50 so this helped, but obviously the rest of the house is still very leaky.

In Mechanicals | Asked By Mark Fredericks | Dec 3 14
60 Answers

Insulating basement rim joist

Hello, without taking too much of your time, can you please just assist me in a recommendation for insulating my basement rim joists? very small basement, very old home, block walls..

In Green products and materials | Asked By Dave Mac | Dec 1 14
17 Answers

Insulating an unheated basement / cellar

Hello everyone,

Thank you for the great site and apologize in advance for lengthy first post.

I have a small room (6'x20') in the basement that is currently unheated and uninsulated under covered porch. Ceiling and walls are concrete and there is no visible water penetration. There is exterior door separating this room from the rest of the finished basement (conditioned/insulated)

In Green building techniques | Asked By Chris kim | Dec 2 14
1 Answer

Why is my roof decking not matching up on the corners of the hip ridge?

I have built a 16'x20' deck with a hip roof and a cupola, on one side my roof decking matches up perfect and on the other side on both ends the plywood runs out and doesn't match the adjacent side. It is the same on both ends on one side 4" long one the 20' side, I started the layout of the decking the same on both sides and one side is good and the opposite side is not. I don't understand this all four ridge boards are the same length and all cut on the same rake.

In General questions | Asked By Chance Bates | Dec 4 14
13 Answers

The dreaded vapor barrier question

let me start by saying i have read almost every single vapor barrier post one this site and many others and am still confused, or over thinking this because im an engineer and thats what we do. It also seems that the answer is a case to case basis so here goes.

I want to finish part of my walk out basement for a play room for my kids and i am concerned with mold/rot problems in the future if not done correctly. I live in central NH which is climate zone 6 and the house is not Air conditioned but is heated and the basement will be heated with a pellet stove.

In Energy efficiency and durability | Asked By Matthew Morrill | Dec 2 14
16 Answers

Found a surprise in the wall on Day 1 of basement reno

Hi all,

In Energy efficiency and durability | Asked By Darcy Grant | Dec 1 14
22 Answers

Plumbing - home run, remote manifold or other design?

I will be remodeling my home which involves relocation of kitchen and baths. I will be running 1" copper to the main manifold, and then I will split off into PEX tubing. I'm getting nearly instant hot water in my current home config (<25 runs through 1/2" pipe). However, I will be nearly doubling the length of my longest runs. In the remodeled home,

- The longest run will be ~50' to the kitchen sink/dishwasher from the water heater
- Master bath will be about ~20' from the water heater
- Kids/guest Bathroom will be about 40' from the water heater


In GBA Pro help | Asked By Brad Stoppenhagen | Nov 29 14
6 Answers

Raft slab detail

I'm trying to get pricing and supply information for a proprietary insulated footer for a raft slab.

I'm in British Columbia. Does anyone know where I can buy such a product locally?

In Green products and materials | Asked By erik olofsson | Apr 1 14
5 Answers

Insulating floor above uninsulated basement

I live in zone 5 in Chicago. I own a house built in 1883. The basement is uninsulated save the rim joists which have been sprayed with closed-cell foam. There are a number of old single-pane windows which I plan to brick in in some locations and replace with glass block in others. My question is whether I should insulate between the joists in the basement ceiling/main floor or proceed more quickly with the window replacement? Or do I just do it all as I am able?


In Energy efficiency and durability | Asked By Robert Hansen | Nov 29 14
4 Answers

Can I use polyiso over cellulose if I paint ceiling with low perm paint?

I thoroughly enjoyed Martin Holladay’s “Musings of an energy nerd” article regarding “Are Dew-Point Calculations Really Necessary?” from 9/17/2010.

There is a little confusion on my end in that the article seems to speak heavily on the wall portion of a house and not so much on the ceiling. Can I substitute ceiling for wall as I read the article?

Also, can you comment on my approach of insulating my attic?

Plan (from inside out):

In General questions | Asked By Brian Rittershaus | Dec 1 14
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