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Insulating an existing house
- Thread starter jar546
- Start date
My interpretation is not necessarily the same as someone elses---and for the most part that is a good thing. My current interpretation only has to be consistant with my past interpretations because, quite frankly, I don't care what anyone else thinks unless I ask them what they think. Codes are a minimum, not a format to slide a bunch of personal bias into the process.
TimNY
REGISTERED
That used to be in our last residential code as N1101.2.1.2. I thought it was a good section.mtlogcabin said:
It is no longer there.
Our new code also exempts any "contributing" building in the historic district from meeting any energy requirement. I asked the State, so if they entirely gut the interior, they don't need to install insulation? They say "the code doesn't cover stupid"
priceless Alias
REGISTERED
Same reply here, it is what it is, do the best you can, and move on. Any additional insulation will only add R-value.fatboy said:
Sue, where the west still lives..............
conarb
REGISTERED
That's not stupid, that's smart, I was called to consult on a job on San Francisco, there was a 100+ year old 900 square foot Victorian home set on a lot, property line to property line on the sides, the city would not allow the home to be torn down or altered in any way, it was raised up on cribbing and a new 6,000 (read $6 million) home was being constructed under and behind the old home so that from the street nobody would know that it was nothing but a 100+ year-old little Victorian, yet inside it would be a modern palace. The side walls were beautiful first growth redwood with no WRB that could not be touched, the question was how to insulate those walls? Anything you put in those walls is going to be subject to wetting and mold growth, closed cell foam was proposed by some but mold grows like crazy in styrofoam. I told them it couldn't be done, to get the city to waive the insulation requirement, which they apparently did. In this slideshow idiots sprayed foam around windows, when I first removed the vinyl strips there were mushrooms growing out of the styrofoam in 5 months big enough to look like the belonged in the produce section of a grocery store, with a disabled guy in a wheelchair in one fo the affected apartments, a lawsuit waiting to happen.Tim said:
With AHJs enforcing these crazy green and energy codes sovereign immunity should disappear and they should be liable for the health and safety problems they are creating, and the inspectors requiring compliance should not be personally allowed to use the defense of "just following orders". The Nuremberg Defense didn't work for the Nazi war criminals, and it shouldn't work for inspectors enforcing codes that are going to harm people either.
MarkRandall
Silver Member
I was wondering the energy interpretation on a recent very small project that is now on hold for awhile. Fits with this discussion, so I'll throw it out.
Project was converting a garage space to a master bedroom. House is less than 10 years old. House is framed with 2x6, garage with 2x4. When converted is less than R-21 or R-19 acceptable? I never got far enough to do code research with WA state energy code, but it sounds like some would allow R-13 and it sounds like the code mtlogcabin references would allow it. Any here who say the walls would need to be furred out to allow R-19 or R21 per the code they use or require some other form of insulation that would comply with higher R values? Please specify code you use in your answers.
Project was converting a garage space to a master bedroom. House is less than 10 years old. House is framed with 2x6, garage with 2x4. When converted is less than R-21 or R-19 acceptable? I never got far enough to do code research with WA state energy code, but it sounds like some would allow R-13 and it sounds like the code mtlogcabin references would allow it. Any here who say the walls would need to be furred out to allow R-19 or R21 per the code they use or require some other form of insulation that would comply with higher R values? Please specify code you use in your answers.
Mark,
I would and have required that a garage conversion to living space meet the energy requirements. Here is my justification:
Look at the "Title, Scope and Purpose" in the Administration chapter of whichever code version you are using.(SectionR101 in the 2006 IRC) R101.2 states "The provisions of the...(code) shall apply to the construction, alteration, movement, enlargement,..." Since the scope of the proposed work is the alteration of the building you have established that the Code applies. Now go to R101.3 Purpose. "The purpose of this code is to provide minimum requirements to safeguard the public safety, health and general welfare through affordibility, structural strength, means of egress facilities, stability, sanitation, light and ventilation, energy conservation,..." Now you have the requirement to enforce whatever energy code you are using on this particular alteration. In my mind this puts the burden on the Ahj to enforce the code requirements for everything spelled out in the applicable codes. By the way, in Minnesota we have a code amendment that replaces the entire Administration chapter with our own wording. It is not much different than the 2006 I codes. We are still on the 2006 I Codes.
Joe
I would and have required that a garage conversion to living space meet the energy requirements. Here is my justification:
Look at the "Title, Scope and Purpose" in the Administration chapter of whichever code version you are using.(SectionR101 in the 2006 IRC) R101.2 states "The provisions of the...(code) shall apply to the construction, alteration, movement, enlargement,..." Since the scope of the proposed work is the alteration of the building you have established that the Code applies. Now go to R101.3 Purpose. "The purpose of this code is to provide minimum requirements to safeguard the public safety, health and general welfare through affordibility, structural strength, means of egress facilities, stability, sanitation, light and ventilation, energy conservation,..." Now you have the requirement to enforce whatever energy code you are using on this particular alteration. In my mind this puts the burden on the Ahj to enforce the code requirements for everything spelled out in the applicable codes. By the way, in Minnesota we have a code amendment that replaces the entire Administration chapter with our own wording. It is not much different than the 2006 I codes. We are still on the 2006 I Codes.
Joe
mtlogcabin
SAWHORSE
Mark
mn joe followed the correct path in his application of the IRC but there is more in the IRC on how to use each chapter effectively. Please read below. The exception I noted above is based on the energy use of the building is not increased: Will converting the garage require additional energy use for the mechanical system. Maybe it is oversized already, might be undersized. Can the attic insulation be increased to make up for what is lacking in the walls. Remember the IRC is prescriptive and not the only way to achieve compliance.
2009 IRC
R104.11 Alternative materials, design and methods of construction and equipment.
The provisions of this code are not intended to prevent the installation of any material or to prohibit any design or method of construction not specifically prescribed by this code, provided that any such alternative has been approved . An alternative material, design or method of construction shall be approved where the building official finds that the proposed design is satisfactory and complies with the intent of the provisions of this code, and that the material, method or work offered is, for the purpose intended, at least the equivalent of that prescribed in this code. Compliance with the specific performance-based provisions of the International Codes in lieu of specific requirements of this code shall also be permitted as an alternate.
2009 IRC
Effective Use of the International Residential Code
Chapter 11 Energy Efficiency. Chapter 11 contains the energy-efficiency-related requirements for the design and construction of buildings regulated under this code. The applicable portions of the building must comply with the provisions within this chapter for energy efficiency. This chapter defines requirements for the portions of the building and building systems that impact energy use in new construction and promotes the effective use of energy. The provisions within the chapter promote energy efficiency in the building envelope, the heating and cooling system, the service water heating system and the lighting system of the building. This chapter also provides energy efficiency requirements for snow melt systems and pool heaters.
Exclusive use of the IRC for energy compliance for alterations limits cost effective ways to achieve that compliance
mn joe followed the correct path in his application of the IRC but there is more in the IRC on how to use each chapter effectively. Please read below. The exception I noted above is based on the energy use of the building is not increased: Will converting the garage require additional energy use for the mechanical system. Maybe it is oversized already, might be undersized. Can the attic insulation be increased to make up for what is lacking in the walls. Remember the IRC is prescriptive and not the only way to achieve compliance.
2009 IRC
R104.11 Alternative materials, design and methods of construction and equipment.
The provisions of this code are not intended to prevent the installation of any material or to prohibit any design or method of construction not specifically prescribed by this code, provided that any such alternative has been approved . An alternative material, design or method of construction shall be approved where the building official finds that the proposed design is satisfactory and complies with the intent of the provisions of this code, and that the material, method or work offered is, for the purpose intended, at least the equivalent of that prescribed in this code. Compliance with the specific performance-based provisions of the International Codes in lieu of specific requirements of this code shall also be permitted as an alternate.
2009 IRC
Effective Use of the International Residential Code
Chapter 11 Energy Efficiency. Chapter 11 contains the energy-efficiency-related requirements for the design and construction of buildings regulated under this code. The applicable portions of the building must comply with the provisions within this chapter for energy efficiency. This chapter defines requirements for the portions of the building and building systems that impact energy use in new construction and promotes the effective use of energy. The provisions within the chapter promote energy efficiency in the building envelope, the heating and cooling system, the service water heating system and the lighting system of the building. This chapter also provides energy efficiency requirements for snow melt systems and pool heaters.
Exclusive use of the IRC for energy compliance for alterations limits cost effective ways to achieve that compliance
MarkRandall
Silver Member
Ah, thanks Mtlogcabin, I did not catch the comment on energy use can not be increased. Whether or not the existing furnace is adequate, it is increasing energy use with about 500 SF of additional heated space. I am aware we could calculate the envelope requirements and probably get by with 2x4 walls. I was thinking prescriptively when asking the question.
JBI
REGISTERED
I have always, consistently, admitted to my mistakes.
I have always, consistently, strived to better at what I do.
I have always, consistently, tried to learn more so that I will make fewer mistakes and be better at what I do.
Being consistant does not mean being stagnant or repeating mistakes.
I have always, consistently, strived to better at what I do.
I have always, consistently, tried to learn more so that I will make fewer mistakes and be better at what I do.
Being consistant does not mean being stagnant or repeating mistakes.
Architect1281
REGISTERED
I TOTALL agree with MTLog Cabin he has it right
problem is contractors and homeowners dont know how to get there
IRC even in appendix is gray
IRC res reads like this
N1101.2 Compliance. Compliance shall be demonstrated by either meeting the requirements of the International Energy Conservation
Code or meeting the requirements of this chapter. Climate zones from Figure N1101.2 or Table N1101.2 shall be used
in determining the applicable requirements from this chapter.
GOING to the International Energy Code GETS you the relief needed
I can't imagine any of us as enforcement would need much convincing that old walls filled with insulation where ther was
formerly zero would use less energy.
problem is contractors and homeowners dont know how to get there
IRC even in appendix is gray
IRC res reads like this
N1101.2 Compliance. Compliance shall be demonstrated by either meeting the requirements of the International Energy Conservation
Code or meeting the requirements of this chapter. Climate zones from Figure N1101.2 or Table N1101.2 shall be used
in determining the applicable requirements from this chapter.
GOING to the International Energy Code GETS you the relief needed
I can't imagine any of us as enforcement would need much convincing that old walls filled with insulation where ther was
formerly zero would use less energy.
TimNY
REGISTERED
I did find that NY added an exception (moved from it's previous location in our last code), that permits the existing cavity to be filled with insulation having a minimum R-value of 4.0/inch. Previous code just said "filled with insulation"; the minimum R-value was added in the newest edition.
JMORRISON
Silver Member
Answer to Mark's question; excerpt from WA state energy code:
101.3.2 Application to Existing Buildings: Additions, historic buildings, changes of occupancy or use and alterations or repairs shall comply with the requirements in the subsections below.
EXCEPTION: The building official may approve designs of alterations or repairs which do not fully conform with all of the requirements of this Code where in the opinion of the building official full compliance is physically impossible and/or economically impractical and:
1. The alteration or repair improves the energy efficiency of the building; or
2. The alteration or repair is energy efficient and is necessary for the health, safety, and welfare of the general public.
In no case shall building envelope requirements or mechanical system requirements be less than those requirements in effect at the time of the initial construction of the building.
101.3.2 Application to Existing Buildings: Additions, historic buildings, changes of occupancy or use and alterations or repairs shall comply with the requirements in the subsections below.
EXCEPTION: The building official may approve designs of alterations or repairs which do not fully conform with all of the requirements of this Code where in the opinion of the building official full compliance is physically impossible and/or economically impractical and:
1. The alteration or repair improves the energy efficiency of the building; or
2. The alteration or repair is energy efficient and is necessary for the health, safety, and welfare of the general public.
In no case shall building envelope requirements or mechanical system requirements be less than those requirements in effect at the time of the initial construction of the building.