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7 Answers

Portland cement?

HI, I have been reading about Portland Cement and was wondering your thoughts. It had been written that it can cause fatigue from standing on it as it draws out the energy just like it can drain a car battery. Also has been known as "new barn" syndrome for animals. German employers actually cut out the cement where their employees stand and put a different product to not cause the fatigue.

In General questions | Asked By Kami Kline | Dec 22 12
6 Answers

When does a new boiler installation legally need a service visit?

Hi guys, Im desperate to find out for my pensioner mum when a new boiler installation legally needs a service. The boiler was installed incorrectly and was checked by another boiler installation company 2 and half years after installation who said that if she hadnt had it checked when she did it could have been deadly. Myself and mum didnt think a brand new boiler installation would need a service for at least the first 2 yrs ( a bit like a new car). Can someone please tell me how long "legally" a new boiler installation needs a service.

In General questions | Asked By angie brook | Dec 22 12
6 Answers

Flash and batt insulation

I have a 100+ year-old home in climate zone 6A (Wisconsin) that needs new sheathing and siding, so I figured I may as well reinsulate the wall cavity as I pull and replace the sheathing (currently has R13 batt in a 2x4 wall cavity). After considering a variety of options, I keep coming back to flash and batt and wonder if this will work for me. Most (all?) flash and batt applications are applied from the interior--that is, 1-2" of closed-cell spray foam is applied to the exterior sheathing, batt insulation is installed, and drywall is put up.

In GBA Pro help | Asked By Eric Rinehardt | Jul 27 12
15 Answers

Locating an HVAC condensate drain in a Passive House

What is the best approach for dealing with condensate drains in a Passive House?

We will have 3 mini split cassettes on the main floor and one for the basement for the Passive House we are building in Maine. See our blog at www.EdgewaterHaus.com.

Options we have considered so far:
- Standard local practice is to bundle the condensate drain with the refrigerant coil and control wires directly outside. Unit drains in summer A/C, not in winter heating so no freezing concern. We don't like this approach because the condensate tube is an air pathway into the house.

In PassivHaus | Asked By Roger Normand | Aug 23 12
1 Answer

How to heat indoor pool and combine with dehumidifier?

To build a small indoor pool, about 12'x16'x4', I need to dehumidify the space and heat the pool water. I would like to combine the two functions with a heat pump that uses hot attic air, feeds the pool heat exchanger and a dehumidifier, hopefully I can use the condensed the output from the dehumidifier to dump it into the pool for an extra bonus. What components should I buy? Thanks for any suggestions!

In Green building techniques | Asked By Johannes Notthoff | Dec 21 12
1 Answer

Rim joist insulation

I have several questions about insulating the rim of the 1st floor platform above the basement of my 2001-built house. I have recently found condensation on the rim joist after cold nights under the squares of the open-faced FG bat that had been shoved between the I-joists. I removed the FG and no longer get condensation, but would like to reinsulate effectively.

I plan on installing rigid foam between the I-joists, and need to determine what R value is appropriate for Northern Colorado.

In Energy efficiency and durability | Asked By William Fryer | Dec 21 12
28 Answers

Larsen truss questions

Hello. I was hoping to get some more feedback from the GBA folk.

We have just framed a small house in an area with a -32 design temperature. our plan is to attach a Larsen truss to a conventionally framed wall. the wall detail is as such: 2x4 stud wall, sheathed with 5/8' t+g OSB, 8"-ish Larsen truss, cross-strapped with 1x, rainscreen, cedar siding. we have to use batt insulation because dense-pack or wet-pack cellulose is not available (we will use blown cellulose for the attic).

In General questions | Asked By erik olofsson | Oct 3 12
1 Answer

Hybrid Wall - Closed Cell Spray Foam Flash w/ Exterior Insulated Sheathing

As I was searching through the various posts related to the use of insulated sheathing on the exterior envelope I have not seen anything for or against the use of exterior insulation in combination with 2# closed cell spray foam (1-2" thick) on the interior cavity. My first thoughts were combination may allow you to reduce the thickness of the exterior insulation, aleviating some of the window/trim detail concerns and still help you reduce the likelihood of the dew point occuring at the sheathing (both are basically vapor impermeable).

In Energy efficiency and durability | Asked By Michael Burke | Dec 20 12
16 Answers

Question concerning condensation

I just moved into a newly constructed house in zone 5A this past October. It has SIP walls, slab on grade (stained & sealed) with radiant and cellulose in the ceiling at R-42.

I know this is a new house and there will be a lot of moisture from the 2x's and drywall that will eventually go away, but it seems that I have a more than average amount. My Pella Proline windows have 20-30% condensation that is dripping all over place. The Therma Tru doors are fine (front and patio), but the brass hardware is dripping wet.

In General questions | Asked By Bud Weiser | Nov 29 12
12 Answers

Best wall system for a 200+ year home?

Hi I am still in the planning phases of designing a home in zone 6. I was recently looking at building a ~R50 double stud wall with a 3/4" rain screen gap clad in fiber cement siding.

I am 27 years old and plan to live in this house for hopefully 50+ years. I would like assistance determining if I am better off with a low maintenance lifetime siding like brick. Since I'm still fairly young does the added initial expense of brick have a favorable return on investment over 50 years or more when passed on into future generations?

In Energy efficiency and durability | Asked By Shane Fairman | Nov 3 12
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