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101 Answers

Water - The Wonder and the Danger

We live on a watery planet. 70% of the earth's surface is water (the same percentage of water in our bodies). It is the font and sustainer of life (SETI looks for water on other planets as the sine qua non of life). So why have our modern "green" building practices turned it into a monster? And how can we stop fighting it and turn it back into an ally?

In Energy efficiency and durability | Asked By Robert Riversong | Nov 28 10
3 Answers

If I don't cool my home on summer, should I think like I'm in a cold climate when I design my wall assembly?

In regards to vapor difussion, in a mixed-humid climate, where no AC will be used in summer, should a Cold Climate wall assembly design work just fine?

In other words, does the special concerns we have to consider when designing a mixed-humid wall assembly, have to do with being able to work succesfully and withstand both heating and cooling seasons? What if I don't have a cooling season (No AC in my home), should I just use a cold-climate approach?

This is for Pucon, Chile, which has a climate like US's 4-C, or Marine.

Thanks.

In General questions | Asked By Jose Castro | Oct 28 14
3 Answers

Heating bathroom and attached closet

We are beginning a long and expensive endeavor to update a 100 year-old house in the Seattle area and first on the list is updating two small bathrooms. The previous owners of the house installed an efficient Buderus boiler a few years ago, but unfortunately the radiators in these rooms have been long been removed. They are currently heated by a few wall-mounted electric space heaters which I would really like to rip out. Unfortunately, I can't seem to get a straight answer from any heating contractors as to how to heat the space adequately and efficiently.

In Mechanicals | Asked By Corey Vanhove | Oct 28 14
4 Answers

Installing ductless minisplit over refrigerator

Building an 800sf 2 story house, main floor is 400sf open floor plan. Would there be any problems if I were to install the ductless mini split head above the refrigerator?

I was thinking of mounting it on the front of the soffit so it would be flush or slightly proud of the front of the fridge, allowing it to spread air down without hitting the fridge. It would also be further from the coils on the back of the fridge. I read that it should be 7-10" below the ceiling.

In Mechanicals | Asked By Tom Frisch | Oct 28 14
7 Answers

Sealing meeting point of brick wall and asphalt driveway

Hi,

My house, a semi-detached, has an asphalt mutual drive between it and the neighbors house to the south that comes right up to the side of the house.

I'm concerned about the meeting point between the asphalt and the brick as it looks like water can collect there and seep into the brick (I have some Interior spalling and suspect that this is the source), but I'm not sure how to address this.

Do I use caulk.. or something with the consistency of tar.. or something like mortar for bricks..?

Some photos here:

In General questions | Asked By Jon Haque | Oct 22 14
1 Answer

Rim joist thermal barrier

The rim joist in my unfinished basement is insulated with 3 inches of rigid polyiso along with one part spray foam to air seal around the edges. My understanding is that building code exempts up to 3 1/4 inches of spray foam in this area from the thermal barrier requirement, but that this exclusion does not apply to rigid foam boards.

In Building Code Questions | Asked By Michael Lee | Oct 27 14
2 Answers

I just received a sample of Tyvek Thermawrap external insulation in the mail

It's being promoted as a vapor permeable alternative to foam board external insulation but I'm feeling dubious about how the installation is supposed to work. Anyone have any experience with this material?

In General questions | Asked By James Morgan | Oct 27 14
4 Answers

Insulating a metal barn

I have read a lot about condensation problems when insulating metal barns, as well as your blogs on bubble wrap scams and subsequent commentary.

In Energy efficiency and durability | Asked By brian mccoy | Oct 27 14
7 Answers

Add R-14 Roxul between the garage attic and the house?

I am currently in the process of insulating my attached garage using Roxul R14 "ComfortBatts". I live in Winnipeg and from experience -- when I did this in my last house -- it can improve the temperature by 10-15 degrees Celsius in the winter, without any heating. (And that was with a non-insulated garage door; my new house has insulated garage doors!)

In Energy efficiency and durability | Asked By Mike Lucas | Oct 23 14
2 Answers

Basement slab retrofit questions

I have an older home built in the 1950’s. I’ve insulated the basement walls with rigid foam and a stud wall with batts. This has made the basement more comfortable, but I still have a lot of moisture in the air based on the dehumidifier that I run frequently. I’m fairly certain that the existing slab must be un-insulated and is missing any poly or other moisture barrier under it.

In Green building techniques | Asked By Mark Fredericks | Oct 27 14
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