Process of renovation & what recommendations can you offer to be energy efficient .
Would like to know what kind of recommendation you can give me on foam insulation for residential home. Colonial Hall built in 1970 and the construction of the frame wall consists of:
The existing exterior wall for the 1st & 2nd floor is made up of 1/2″ gypsum wallboard, 2 X 4 (3 1/2″) wood frame with R-11 fiberglass insulation, along with 1/2″ fire retardant material (Black material), with 2″ void or dead air space and then with 3 3/4″ block concrete with stucco as the exterior material.
1/2″ gypsum board (Sheet rock)
3 1/2″ 2 X 4 Wood Frame with R-11 Fiberglass Insulation
1/2″ Fire Retardant Material
2″ Void Dead Air Space
3 3/4 Stucco over Concrete Block
Total — 10.25″ Wall Construction
Let’s still look at all options increasing the walls with either fiberglass, foam, or rigid foam board over stucco which 1″ is equal to R-5 in which to get to R-22 for the existing walls.
Which would you recommend putting foam insulation in the void and how would go about it?
The other question do you do energy modeling & HVAC design and if not who would you recommend?
This project is about to begin soon meaning I am adding on a new kitchen, family room, mud room, new three door garage and above new master bedroom and renovating the second floor and roughing out attic with 3 dormers and two shed dormers in the back.
If there is any interest in this project let me know so I can send the pdf file to you. We are in the process of getting the building permit any day now.
My ideal of this project is to have geothermal heat pump and net zero application as much as possible no real green except the walls with foam etc.
Presently the attic roof floor is R-19, existing walls r-11, basement r-11. Would like to install R-38 in the attic roof, R-22 walls, and all the new renovation will be up to code.
Don’t hesitate to contact me via email look forward to your answers.
Thank you,
Peter Zelov
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Replies
Peter,
You clearly need a good local energy-efficiency consultant. This is a public question and answer forum, not a professional consultancy.
But you cannot fill the drainage cavity behind the block and stucco. That is necessary for any masonry cladding to prevent radiant-driven and wind-driven moisture from diffusing into the structural frame and thermal envelope.
Peter,
This is an informational Web site, not an energy consulting company. The Green Building Advisor Web site does not offer "energy modeling & HVAC design."
You have several options to contract for these services. You need to hire either:
1. A BPI-certified or RESNET-certified energy auditor;
2. An HVAC engineer;
3. An architect; or
4. All three.
What would you recommend in insulating between the 2X4 would you gut the walls and spray in foam to get to R-22 with open cell foam and reclose the walls with sheetrock etc.
Peter,
Your choice of insulation depends on your goals. Filling the bays between 2x4 studs will never yield a high-performance wall, no matter what insulation you use, for two reasons:
1. The wall thickness is only 3.5 inches -- that's not much -- and
2. Each stud acts as a thermal bridge.
Closed-cell spray polyurethane foam will yield the highest R-value per inch, but it will not address the thermal bridging.
A continuous layer of rigid foam covering all of the studs will perform much better than any product inserted between the studs.
We just did a major remodeling project (Minnesota) and didn't mess with the existing walls except to remove all the stucco, repair damaged sheathing, and install traditional asphalt-based building paper and new cement-board siding.
For the roof and dormers, however, we were able to foam the new walls and add 8" joists over the old roof, leaving in place the existing 1953 era 2" x 4" joists. This got us up to an R-40 or so, and ventilated the roof property from the soffts (which were increased to overhang by 16").
We put money into triple paned windows, and also REDID the foundation around the finished basement with exterior foamboard, new waterproofing, and draintile. The basement is now warmer, less humid, and ready for the next 50 years.
We are thinking of re-stuccoing the outside of the orginal stucco to match with the new renovation do you have any other thoughts in addition to question #5.
Pete
If you want energy efficiency you need to put the project on hold and get some help. The GEO is the wrong place to put money unless you have seriously improved the air tightness and insulation of the existing home and addition.
You throw around R 11 and r19 r38 etc. Are these the combined values of the materials or is it the installed effective value. I will go with the first. Without air sealing your insualtion values are much lower than the stated R value of the material. You also have to worry about mold issues too.
You can not cost effectively go back and make your home energy efficient and comfortable after the remodel. Do it now.
Something I would worry about it if you make the addition a lot tighter and more energy efficient is that you will not have a comfortable house. Heat pump puts out cold air when compared to gas heat. You may end up with comfort problems and find the geo running al the time trying to keep up.
I would get an energy audit on the existing home and come up with plan to make the home more efficient and compatible with the addition. The work can be done in conjunction with the remodel.
You will likely save money on the GEO as they are costly and you will get a HVAC system correctly sized. This will make the system operate more efficiently and last longer.
Keep this in mind. Air sealing and proper insulation should be at the top of your list. In most cases it is better to the money into the shell before spending a lot on a GEO unit.
I want to increase from R-11 to R-22 with the orginal structural walls and what are any recommendations do you have in doing so please see the orginal question and what do you suggest to do when we re-stuccoing when all is done and planning to insulate old section and new roof with R-38 or 40 too. Replacing are new windows with Low-e insulated glass which will be Marvin.
Peter,
Do you have an architect or a designer yet? In your e-mail to GBA, you wrote, "I would like an answer soon. It’s in the stages of getting a building permit."
It sounds like you are rushing things. If you are getting a building permit for a project which includes increasing the wall R-value from R-11 to R-22, but you still don't know where you are going to be placing your insulation, it sounds like you are not ready for a building permit yet.
You need to hire an architect or a residential designer.
I have one in place and everything is ready to go. All I want to know from you is what recommendations can I do to increase the insulation from R-11 to R-22 in the original walls etc.
Peter,
Why don't you simply ask the architect that question -- or just read the plans? If you have an architect who has designed R-22 walls for you, then these insulation details will be shown on the plans.
However, if your architect can't answer the question, it's clearly time to switch architects.