Wall Anatomy – Efficiency & Elim. Mold
We are in the design phase of a new home just under 4,000 square feet excl. basement. Location is Hudson Valley, NY. Temps range from -10 to 100 with humidity levels running the range as well. Summer days can be very hot and humid for a couple weeks at a time. They can also be more pleasant and drier. Winters can be snow, rain, lots of temperature variations.
House is stone, brick and tudor; 2-story with finished attic space over one section. Lots of windows, top of hill with nice views, but lots of wind. Full basement, part of which may be finished at some future date.
Trying to decide on wall structure and HVAC system. Concerns are energy efficiency, mold issues and environmental – healthy house, chemicals.
Considering Geothermal with radiant floor heat. Will have a supplemental wood stove in family room. Not great fan of air conditioning — like to open windows, but are considering due to dehumidification and mold concerns in light of modern air tight construction. Heat exchange ventilation system a definite.
Had one recommendation from an HVAC guy to use forced hot air as the same duct system can handle heat, cooling(dehumidification), ventilation and filtering. Much less expensive. What about comfort factor? Heard radiant is more comfortable at lower temperature than air.
Trying to decide on wall structure and insulation. Thinking about ICF’s for basement and first floor. Maybe aerated concrete blocks, or wood fiber blocks with concrete poured inside (Durisol from Canada). 2nd floor wood frame due to complexity of structure and dormers etc. Insulation — Icynene or similar open cell spray material, closed cell material, wet pack cellulose, SIPS (structure may be too complicated), etc. Similar materials in roof. Steep roofs with dormers. Big concern is understanding that the goal is to keep water out, but the likelihood is that some will get in. What is the best way to allow the wall cavity to dry out and reduce the chance of mold and rot? Read about system of air cavity between siding and wall structure to allow wall to dry. Especially needed with brick/stone/concrete siding. What about vapor barriers — concern is condensation when moisture hits cold barrier and condenses. What is wrong with the old felt paper where the water sheds from the outside, yet it is permeable to vapor. I am concerned that some of these wall wraps don’t breathe as they should.
Very interested in hearing from someone who has been living in a house constructed with some of these materials for several years. Long enough to see how they work in the real world.
Replies
Greetings T, as a first time poster Welcome to Breaktime.
This post, in response to your question, will bump the thread through the 'recent discussion' listing again.
Perhaps it will catch someones attention that can help you with advice.
Cheers
'Nemo me impune lacesset'
No one will provoke me with impunity
Good an advanced search on persist (wall systems).
If you google PERSIST along with insulation, membrane, foam, you will learn about the safest and perhaps the best performing wall system ever developed. After you see what it is, I can answer your questions about how to implement it. Good luck.
Google a product called Greenkrete. This block is supposedly r3.5 per inch and completely load bearing. No concrete cores to fill. Something like AAC except better. I just found this product myself, and would like to know what others looking at the site may think.