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4 Answers

Which one is better: Using salt-based water softeners or salt-free water conditioners?

I am building a new house and don't know which one to buy.

In General questions | Asked By tania jalil | Jun 17 12
6 Answers

Should I caulk the bottom of vertical cedar siding?

A contratoor who replaced some wood pecker damaged vertical cedar siding boards recommended that I caulk at the bottom of the lowest boards as a way to lessen air inflitration into my home. House was built in 1987 and has Celotex sheathing on the outside of the stud walls with the cedar siding over that. I think that caulking as he recommends will only trap water behind the siding that can get in where the boards overlap.

In Energy efficiency and durability | Asked By James Manor | Jun 22 12
2 Answers

New construction crawl space design

Getting ready to pour my foundation with crawlspace. for a small building. Site appears well drained. This is in zone 6.

3" XPS will be put on outside of foundation with drains installed at footings. Not planning on insulating the main floor of living space. 2"x 6" construction with 3" XPS all the way up the outside with blown in cellulose in stud wall. (24" OC construction).

In Energy efficiency and durability | Asked By brenda field | Jun 24 12
2 Answers

Do I need Tyvek?

I'm retrofitting a 1952 ranch stye house in Connecticut. The wall sheathing is 1x6 tongue and groove. I'm going to put two layers of 1 3/8" polyiso on the exterior.

Sheathing is now covered with tar paper. I'm thinking of taking of the tar paper (its damaged on a lot of areas) then install polyiso over the sheathing without any Tyvek - Each sheet of polyiso will be caulked around the perimeter. Interior walls ares stripped and will be dense packed with cellulose.

In Energy efficiency and durability | Asked By Walter Gayeski | Jun 24 12
6 Answers

Ever a good idea to install a powered roof vent?

I know these powered roof vents get a bad rap, but is it ever a good idea to install them?

Such as if the attic floor (ceiling below) has been air sealed. This way the powered roof vent should not be pulling conditioned air from the house, rather it's pulling mainly from the soffits or other areas of easy entry.

Also assuming, the power roof vent is temperature controlled and electric efficient.

Zone 4 represented


In Energy efficiency and durability | Asked By Mark Lancaster | Jun 22 12
5 Answers

Interior basement wall insulation - options after framing has started

So, we decided late in the building process to finish some of the basement. I forgot to specify that rigid foam be applied to the interior basement wall, and the interior framing has already been done. I'm still kicking myself for the oversight. I'm sure the builder is planning to go with 'code' and put in fiberglass insulation in between the studs against the concrete wall.

So...what options do I have at this point to minimize future moisture problems. I can specify paperless drywall. Might be able to get rigid foam cut and applied between the studs.

In Green building techniques | Asked By Bryan Anderson | Jun 22 12
1 Answer

Basement floor detail — 1896 New England renovation

I'm preparing to renovate the basement of an 1896 Cambridge MA residence. The foundation is classic brick on stone. The stone is 2-3 feet at the base. The existing floor is hugely degraded 2" thick concrete poured on soil full of dense clay. It is always moist, though there is little standing water. I would like to remove the old floor and as much soil as I can safely take out so as to build up a new insulated slab as per attached plan.

A few questions:

In Plans Review | Asked By Jason RosenJasonR | Jun 22 12
3 Answers

What's the best kind of damper to install on a kitchen exhaust fan?

Luckily, my clients trust me and declined to order a huge 1600 CFM kitchen exhaust fan, and settled on a 3 stage fan with a maximum of 400 CFM. I'd like to install a damper somewhere, but I'm running into two issues: First, it seems that building code here in NJ does not allow for an inline damper to be installed (I think). I searched for wall termination louver type dampers, but this fan is not powerful enough to open them (they are typically used in commercial or industrial applications).

In Green building techniques | Asked By Armando Domingos | Jun 15 12
3 Answers

Is there a tankless venting equivalent of drainwater waste recovery devices?

I was looking at wastewater heat recovery systems that wrap around the drain pipe. It got me a wondering - if my tankless exhaust gets so hot that I have to buy very special wall thimbles so it won't start my house on fire, why shouldn't one be able to tap into that?

The exhaust is already fan forced and slopes upward - is there still some minimum operating temperature needed for exhaust to function?

In General questions | Asked By Taylor Bryant | Jun 21 12
10 Answers

Should we install a rainscreen in a 10" wall assembly?

We are building a new home in SE Washington state with 10" thick walls and wondered if we need to worry about having a rainscreen behind the James Hardi lap siding. We get 17-20" of rain here annually and have heard conflicting thoughts about whether it is needed in this climate. We just don't want to end up with any moisture in the wall cavity, but are not sure where it would come from. Here are the details of the wall assembly:

Benjamin Obdyke's Hydrogap housewrap or Sto Gaurd's liquid applied WRB over 1/2" plywood.

In Energy efficiency and durability | Asked By Mark Porter | May 24 12
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