Sealing/encapsulating crawl space
#1
03-08-10, 06:28 AM
Sealing/encapsulating crawl space
Hello all!
New member, have been reading and enjoying the forum. I have a fairly extensive post here.
I have been researching sealing/encapsulating of crawl spaces and think it would be beneficial, but I want some real world input based on those who have first hand experience with it (done it themselves or witnessed the effects). Here's my situation:
Central Arkansas area, very hot and humid summers. House is pier and beam, cinderblock foundation walls, ~2800 sq ft dirt crawl, 6 mil plastic liner on ground, but not overlapped/tightly sealed. Sixteen 8X16 vents along perimeter, R-19 batts in floor and rim joists. Crawl does not accumulate any water. No hvac/electrical in crawl.
Humidity and temps as follows:
Summer
Rh 75-80% in crawl, 70-80% in house. House set @ 78F, crawl temps 5-10 deg below house
Winter
Rh 65-70% in crawl, 35-40% in house. House set @ 69F, crawl temps 15-30 deg below house
Based on my reading, my plan is the following:
1)Replace the current vapor barrier with minimum 6 mil reinforced poly, sealing all seams and attaching 2ft up each wall/pier.
2)Seal the perimeter vents with rigid foam and sealant
My intended results would be:
1)Reduce/more tightly control humidity fluctuations, improving comfort in the summer, and,
2)Increase the winter crawl temps, warmer floors, etc.
But I have some questions...many sites indicate conditioning the crawl with active HVAC supply/return vents or passive vents.
1)Would I have to condition the crawl once I seal it? Wouldn't the add'l space put greater load on my HVAC system, and make it work harder/less efficiently?
2)What would the considerations be for opening a return air vent to the crawlspace after sealing, for use during the summer? I would think drawing cooler air would make the system more efficient, if the humidity was controlled.
3)Would there be substantial benefit to placing rigid foam on the foundation walls? The cost would be at least $400, would I see significant results, esp since the joists are already insulated?
Any thoughts or suggestions on this would be greatly appreciated.
New member, have been reading and enjoying the forum. I have a fairly extensive post here.
I have been researching sealing/encapsulating of crawl spaces and think it would be beneficial, but I want some real world input based on those who have first hand experience with it (done it themselves or witnessed the effects). Here's my situation:
Central Arkansas area, very hot and humid summers. House is pier and beam, cinderblock foundation walls, ~2800 sq ft dirt crawl, 6 mil plastic liner on ground, but not overlapped/tightly sealed. Sixteen 8X16 vents along perimeter, R-19 batts in floor and rim joists. Crawl does not accumulate any water. No hvac/electrical in crawl.
Humidity and temps as follows:
Summer
Rh 75-80% in crawl, 70-80% in house. House set @ 78F, crawl temps 5-10 deg below house
Winter
Rh 65-70% in crawl, 35-40% in house. House set @ 69F, crawl temps 15-30 deg below house
Based on my reading, my plan is the following:
1)Replace the current vapor barrier with minimum 6 mil reinforced poly, sealing all seams and attaching 2ft up each wall/pier.
2)Seal the perimeter vents with rigid foam and sealant
My intended results would be:
1)Reduce/more tightly control humidity fluctuations, improving comfort in the summer, and,
2)Increase the winter crawl temps, warmer floors, etc.
But I have some questions...many sites indicate conditioning the crawl with active HVAC supply/return vents or passive vents.
1)Would I have to condition the crawl once I seal it? Wouldn't the add'l space put greater load on my HVAC system, and make it work harder/less efficiently?
2)What would the considerations be for opening a return air vent to the crawlspace after sealing, for use during the summer? I would think drawing cooler air would make the system more efficient, if the humidity was controlled.
3)Would there be substantial benefit to placing rigid foam on the foundation walls? The cost would be at least $400, would I see significant results, esp since the joists are already insulated?
Any thoughts or suggestions on this would be greatly appreciated.
#2
03-08-10, 07:12 AM
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Conditioned Crawlspace
What you are describing is an unvented or 'conditioned crawlspace'.
And by definition, this type of crawlspace must be 'conditioned' to be installed.
'Conditioning' means heating and/or cooling and/or dehumidfying the space...so there is no getting around that requirement.
How you choose to condition the space remains the option.
Conditioning a space can be done actively using mechanical means to heat/cool/dehumdify it...or it can be done passively by connecting this space to an already conditioned space....which is usually done by providing vents between the existing conditioned space of the house and the crawlspace.
--------------
All that said, and to answer your questions in order:
1. Conditioning a crawlspace requires sealing it and heating/cooling/dehumdifying it. Conditioned clawlspaces have been tested and proven to cause heating systems to run more efficiently and will use less energy than if you insulate the floors above the basement or crawlspace alone.
2. You cannot have ventilation to the exterior with a closed/crawlspace design. Period. Your thinking is wrong about opening vents in the summer. The exact opposite practice needs to occur in summer. In summer, exterior air is warmer and more humid than basement or crawlspace surfaces. One should always therefore close vents to the outside in summer. Why? Because allowing this warm/humid air to enter will cause it to condense on the cooler interior surfaces promoting wood rot and mold growth.
3. Conditioned crawlspace design requires that the walls be insulated and the ceiling of the crawlspace (floor above) be uninsulated. This means you must remove any insulation in the floor/ceiling assembly and only have insulation on the crawlspace walls and rim joists for this design to work.
But using foam insulation on the crawlspace creates problems for both active and passive conditioning, however.
Because foam insulation is flammable, it must be thermally isolated from the rest of the house.
If you use foam insulation in the crawlspace you cannot passively condition or actively condition the crawlspace if it is used as a plenum unless you also install a thermal barrier over the foam to prevent ignition in a fire.
This is required to prevent flame spread and noxious fumes from communicating with the rest of the house through open vents or air returns.
An approved thermal barrier is 1/2" drywall.
------
Summary:
-Closed crawlspaces must have walls insulated, not ceilings
-Closed crawlspaces must be 'conditioned'.
-Closed crawlspaces cannot be vented to the exterior.
-Foam insulation used in a closed crawlspace must be covered with a thermal barrier to prevent ignition in a fire.
And by definition, this type of crawlspace must be 'conditioned' to be installed.
'Conditioning' means heating and/or cooling and/or dehumidfying the space...so there is no getting around that requirement.
How you choose to condition the space remains the option.
Conditioning a space can be done actively using mechanical means to heat/cool/dehumdify it...or it can be done passively by connecting this space to an already conditioned space....which is usually done by providing vents between the existing conditioned space of the house and the crawlspace.
--------------
All that said, and to answer your questions in order:
1. Conditioning a crawlspace requires sealing it and heating/cooling/dehumdifying it. Conditioned clawlspaces have been tested and proven to cause heating systems to run more efficiently and will use less energy than if you insulate the floors above the basement or crawlspace alone.
2. You cannot have ventilation to the exterior with a closed/crawlspace design. Period. Your thinking is wrong about opening vents in the summer. The exact opposite practice needs to occur in summer. In summer, exterior air is warmer and more humid than basement or crawlspace surfaces. One should always therefore close vents to the outside in summer. Why? Because allowing this warm/humid air to enter will cause it to condense on the cooler interior surfaces promoting wood rot and mold growth.
3. Conditioned crawlspace design requires that the walls be insulated and the ceiling of the crawlspace (floor above) be uninsulated. This means you must remove any insulation in the floor/ceiling assembly and only have insulation on the crawlspace walls and rim joists for this design to work.
But using foam insulation on the crawlspace creates problems for both active and passive conditioning, however.
Because foam insulation is flammable, it must be thermally isolated from the rest of the house.
If you use foam insulation in the crawlspace you cannot passively condition or actively condition the crawlspace if it is used as a plenum unless you also install a thermal barrier over the foam to prevent ignition in a fire.
This is required to prevent flame spread and noxious fumes from communicating with the rest of the house through open vents or air returns.
An approved thermal barrier is 1/2" drywall.
------
Summary:
-Closed crawlspaces must have walls insulated, not ceilings
-Closed crawlspaces must be 'conditioned'.
-Closed crawlspaces cannot be vented to the exterior.
-Foam insulation used in a closed crawlspace must be covered with a thermal barrier to prevent ignition in a fire.
#3
03-08-10, 08:14 AM
manhattan,
Thanks for the input. I know that you cannot have exterior venting to the crawl once it is sealed. What I was referring to was an HVAC return from the crawlspace. This is the recommended solution by some, while others indicate you can use a stand-alone dehumidification system without constructing direct airflow ducts between the living space and the crawl.
That part about the thermal barrier is interesting. A number of the sites that offer products/services for sealing don't mention/show the need for that barrier. I haven't seen a lot of discussion regarding thermal barriers for rigid foam insulation in sealed crawlspaces.
I hate the thought of having to pull out the existing insulation, placing the foam, and then having to cover the foam with drywall or other barrier. And unless I do all those things, you don't see a benefit to sealing it as I outlined?
Thanks for the input. I know that you cannot have exterior venting to the crawl once it is sealed. What I was referring to was an HVAC return from the crawlspace. This is the recommended solution by some, while others indicate you can use a stand-alone dehumidification system without constructing direct airflow ducts between the living space and the crawl.
That part about the thermal barrier is interesting. A number of the sites that offer products/services for sealing don't mention/show the need for that barrier. I haven't seen a lot of discussion regarding thermal barriers for rigid foam insulation in sealed crawlspaces.
I hate the thought of having to pull out the existing insulation, placing the foam, and then having to cover the foam with drywall or other barrier. And unless I do all those things, you don't see a benefit to sealing it as I outlined?
#4
03-08-10, 09:10 AM
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Closed CrawlSpace
RegNurse asked: "I hate the thought of having to pull out the existing insulation, placing the foam, and then having to cover the foam with drywall or other barrier. And unless I do all those things, you don't see a benefit to sealing it as I outlined? "
There is no benefit to what you propose without pulling out the ceiling insulation, insulating the walls, and sealing as required...because without doing all these things, you don't end up with a "conditioned" crawlspace and just waste your money.
"I know that you cannot have exterior venting to the crawl once it is sealed. What I was referring to was an HVAC return from the crawlspace. This is the recommended solution by some, while others indicate you can use a stand-alone dehumidification system without constructing direct airflow ducts between the living space and the crawl."
You can use a stand alone separate conditioning system for a closed crawlspace or you can tie into the existing one. You can have communicating passive vents or an air return as you describe to condition a crawlspace, but if you insulate the walls with foam insulation, the only way you can keep these vents is to place a thermal barrier over the foam. Otherwise you will need to insulate the walls with something other than foam insulation or condition the crawlspace separately from the rest of the house...like by installing its own separate heating/cooling/dehumidying system.
You can find the flamability issue of foam insulation adressed in building codes and the restrictions placed on using foam in insulated crawlspace walls when used as a plenum or ducts in mechanical codes.
Consult your local building code office before you do anything.
Luck
There is no benefit to what you propose without pulling out the ceiling insulation, insulating the walls, and sealing as required...because without doing all these things, you don't end up with a "conditioned" crawlspace and just waste your money.
"I know that you cannot have exterior venting to the crawl once it is sealed. What I was referring to was an HVAC return from the crawlspace. This is the recommended solution by some, while others indicate you can use a stand-alone dehumidification system without constructing direct airflow ducts between the living space and the crawl."
You can use a stand alone separate conditioning system for a closed crawlspace or you can tie into the existing one. You can have communicating passive vents or an air return as you describe to condition a crawlspace, but if you insulate the walls with foam insulation, the only way you can keep these vents is to place a thermal barrier over the foam. Otherwise you will need to insulate the walls with something other than foam insulation or condition the crawlspace separately from the rest of the house...like by installing its own separate heating/cooling/dehumidying system.
You can find the flamability issue of foam insulation adressed in building codes and the restrictions placed on using foam in insulated crawlspace walls when used as a plenum or ducts in mechanical codes.
Consult your local building code office before you do anything.
Luck
#5
03-08-10, 11:12 AM
Member
In know way would I recommend conditioning a crawl space unless it is only a couple of years old. Or with out a major clean up of everything. Don't think you would like all that dirt, bugs, mold etc in the home. I would seal it up and at the most put a dehumidifier in.
#6
03-08-10, 08:49 PM
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Except...
Except that what airman.1994 suggests violates pretty much every building, energy or mechanical code when it comes to installing a closed crawlspace... and is not permitted anywhere....
And you get no bugs, dirt or mold with a properly installed conditioned crawlspace.
And you get no bugs, dirt or mold with a properly installed conditioned crawlspace.
#7
03-09-10, 12:46 PM
Member
Originally Posted by manhattan42
Except that what airman.1994 suggests violates pretty much every building, energy or mechanical code when it comes to installing a closed crawlspace... and is not permitted anywhere....
And you get no bugs, dirt or mold with a properly installed conditioned crawlspace.
And you get no bugs, dirt or mold with a properly installed conditioned crawlspace.
#8
03-10-10, 12:27 PM
insulating a home.
The problem is the heat provided by the sun, due to conduction through the fabric of the home.
This is made worse by the wind carrying the heat under the floor through the crawl space.
If you close off the crawl space, stop the warm air from blowing through, you will benefit from the fact that heat always moves to cold, and some of your heat will move downwards into the ground.
However, you have insulation between the joists so that doesn't happen, except through the joists, your weak link.
It is good that you have provided temperatures as well as relative humidity. The humidity and temperatures quoted in the crawl are not high enough to present a problem.
The humidity and temperature in the home is satisfactory and is not a problem.
There is no need to improve the vapour barrier on the floor of the crawl space. Plastic sheet is an almost water vapour proof product, replacing it with something thicker will not make any difference.
Note. Water vapour always moves from hot to cold and water vapour in the air will only turn into condensation when warm air meets a cold surface, or the air temperature drops.
As the ground in the crawl space is colder than the air in the crawl space and definitely colder than the wood joists there is nothing here to be concerned with. The water vapour in the ground will not rise up and enter the air above.
The floor joists will always be warmer than the air in the crawl space, due to the radiation and conduction of heat from the room above.
Note. At 69f 35-40% relative humidity is low. If you are saying that the crawl is 65 - 70% at 39f, this is very low......there is hardly any water vapour in the air below 40%RH.
I. Improve comfort in home by painting the roof and outside walls white. A white house reflects more heat back into the sky. Plant trees to acquire shade. Block air vents in crawl space to stop warm air heating floor joists and heating rooms above by conduction. And cold air cooling joists and cooling rooms above.
2.About two hundred times a year, there is a warm wind, that finds its way into the crawl space, this wind will be warmer than the ground and warmer than your block walls. When this warm wet air hits your crawl space you will have condensation inside or on the smooth surfaces, if the temperature difference is great enough (the plastic). Blocking the vents will solve this problem.
3. No. You should concentrate your insulation around the perimeter of the comfort zone. Preferably on the inside of all your rooms. This will keep the heat out. Blocking the path of heat into the home by conduction and keep the heat in during the winter.
This is made worse by the wind carrying the heat under the floor through the crawl space.
If you close off the crawl space, stop the warm air from blowing through, you will benefit from the fact that heat always moves to cold, and some of your heat will move downwards into the ground.
However, you have insulation between the joists so that doesn't happen, except through the joists, your weak link.
It is good that you have provided temperatures as well as relative humidity. The humidity and temperatures quoted in the crawl are not high enough to present a problem.
The humidity and temperature in the home is satisfactory and is not a problem.
There is no need to improve the vapour barrier on the floor of the crawl space. Plastic sheet is an almost water vapour proof product, replacing it with something thicker will not make any difference.
Note. Water vapour always moves from hot to cold and water vapour in the air will only turn into condensation when warm air meets a cold surface, or the air temperature drops.
As the ground in the crawl space is colder than the air in the crawl space and definitely colder than the wood joists there is nothing here to be concerned with. The water vapour in the ground will not rise up and enter the air above.
The floor joists will always be warmer than the air in the crawl space, due to the radiation and conduction of heat from the room above.
Note. At 69f 35-40% relative humidity is low. If you are saying that the crawl is 65 - 70% at 39f, this is very low......there is hardly any water vapour in the air below 40%RH.
I. Improve comfort in home by painting the roof and outside walls white. A white house reflects more heat back into the sky. Plant trees to acquire shade. Block air vents in crawl space to stop warm air heating floor joists and heating rooms above by conduction. And cold air cooling joists and cooling rooms above.
2.About two hundred times a year, there is a warm wind, that finds its way into the crawl space, this wind will be warmer than the ground and warmer than your block walls. When this warm wet air hits your crawl space you will have condensation inside or on the smooth surfaces, if the temperature difference is great enough (the plastic). Blocking the vents will solve this problem.
3. No. You should concentrate your insulation around the perimeter of the comfort zone. Preferably on the inside of all your rooms. This will keep the heat out. Blocking the path of heat into the home by conduction and keep the heat in during the winter.
#9
12-24-10, 05:32 AM
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HI All,
Wanted to bump this up. I was wondering two things:
1. If you insulate crawl space walls with polyiso with the foil side in, seal with appropriate tape (hmmm..what kind?) will this prevent any fire hazard issues.
2. My addition has two steam radiators on each side, one is far back to the outside wall to the far right, the other is to the outside wall about 4 feet in, so steam pipes run thru the floor of the addition. We also have two access panels (almost 2 x 4 feet) from the main full basement which is fairly warm due to steam boiler running and uninsulated heating pipes.
So the question is: Are these steam pipes enough to consider the space heated/conditioned?
FYI: My addition is 12 feet out & 25 feet wide.
We are freezing in this house ever since the addition was added. We closed up the vents, but left the floor insulation in. Cinderblock 2' high walls all around, 2" concrete so no dirt.
Thank you all in advance!!!!
Annie
Wanted to bump this up. I was wondering two things:
1. If you insulate crawl space walls with polyiso with the foil side in, seal with appropriate tape (hmmm..what kind?) will this prevent any fire hazard issues.
2. My addition has two steam radiators on each side, one is far back to the outside wall to the far right, the other is to the outside wall about 4 feet in, so steam pipes run thru the floor of the addition. We also have two access panels (almost 2 x 4 feet) from the main full basement which is fairly warm due to steam boiler running and uninsulated heating pipes.
So the question is: Are these steam pipes enough to consider the space heated/conditioned?
FYI: My addition is 12 feet out & 25 feet wide.
We are freezing in this house ever since the addition was added. We closed up the vents, but left the floor insulation in. Cinderblock 2' high walls all around, 2" concrete so no dirt.
Thank you all in advance!!!!
Annie
#10
12-24-10, 06:39 AM
Welcome to the forums! Is the insulation you mentioned between the floor joists? How airtight is the crawl? The steam pipes themselves won't classify it as a "heated" area. Those pipes are carrier pipes. Insulating the pipes would help keep the steam from radiating in the crawlspace before it gets to your radiators.
How thick are your walls of the addition? How much insulation was placed in these walls (R factor), and how was it sealed against the old structure?
How thick are your walls of the addition? How much insulation was placed in these walls (R factor), and how was it sealed against the old structure?
#11
12-25-10, 05:50 AM
Polyiso will not do anything to prevent a fire.
Keeping in mind what you write about the crawl space
there would appear to be little there to burn. What is
the point of adding insulation to the crawl space
walls? What are you trying to do?
Do you have any flammable items down there?
Someone (You?) must have agreed the specification
of the addition? They and the designer and builders
must know how well it was designed and intended to
be built?
Here are some thoughts on what would/should be
considered before designing and building.
You may well have an idea as to how you will use the
extra room, but subsequent owners may use it for
other purposes, has that been taken into account?
How cold has it been in your area during the past 100 years?
How warm do you want to be at that outside coldest temperature?
What leeway was added in for the colder weather we will have over the next 500 years?
What is the maximum amount of rain you've had, the strongest wind?
What type of roof do you need to best cope with the snow, rain and wind?
How should it be insulated to provide the cheapest running cost?
Should you have a Welsh slate roof good for 400 years, or something cheaper that will last five minutes?
Should you have a brick cavity wall, that's fire proof,
insect and critter proof and will be warm and last for
two thousand years.
Would it have been more cost effective and better to
have a solid concrete floor, that is well insulated and
will never be cold?
Would having a concrete floor, with built in under
floor heating, be easier to live with, give you clear
uncluttered walls and more flexible use for the room.
All these things must have been considered along
with their cost.
Did you not watch them build it? Did you not see what
they used, did they appear old enough to have
experience and to know what they were doing?
Did the boiler keep the home warm as it was?
Did you buy a bigger boiler to cope with the addition?
Was the boiler running flat out in previous winters?
Or was it able to cope when running at medium
output, and had spare capacity to heat the addition?
Without knowing how high the ceiling is or how it was
built and how well it is insulated helping is a trifle
difficult.
A typical addition, of that size and of reasonable
specification would need 3 to 4 Kw./10,236 to 13,648 Btu to maintain a comfortable temperature.
Do you need a warm basement?
Was it explained how much heat is lost by heating a
basement, that you do not live in, and how much this
will cost you year after year and what impact this has
on heating the parts of the home you do use?
How much heat is lost from uninsulated pipes and
how this effects the radiators and the cost of heating
your home.
Who decided that the heat output from the radiators
could cope with the amount of insulation fitted in the
walls and floor in really cold weather.
You will end up with two choices.
To increase the heat input....and forever waste
money on heating that will get more expensive year
on year.
To seal all the holes in your home that let your warm
air out and cold air in and to improve the insulation.
This latter process will be a one off cost, that will
save you a fortune over the years.
Keeping in mind what you write about the crawl space
there would appear to be little there to burn. What is
the point of adding insulation to the crawl space
walls? What are you trying to do?
Do you have any flammable items down there?
Someone (You?) must have agreed the specification
of the addition? They and the designer and builders
must know how well it was designed and intended to
be built?
Here are some thoughts on what would/should be
considered before designing and building.
You may well have an idea as to how you will use the
extra room, but subsequent owners may use it for
other purposes, has that been taken into account?
How cold has it been in your area during the past 100 years?
How warm do you want to be at that outside coldest temperature?
What leeway was added in for the colder weather we will have over the next 500 years?
What is the maximum amount of rain you've had, the strongest wind?
What type of roof do you need to best cope with the snow, rain and wind?
How should it be insulated to provide the cheapest running cost?
Should you have a Welsh slate roof good for 400 years, or something cheaper that will last five minutes?
Should you have a brick cavity wall, that's fire proof,
insect and critter proof and will be warm and last for
two thousand years.
Would it have been more cost effective and better to
have a solid concrete floor, that is well insulated and
will never be cold?
Would having a concrete floor, with built in under
floor heating, be easier to live with, give you clear
uncluttered walls and more flexible use for the room.
All these things must have been considered along
with their cost.
Did you not watch them build it? Did you not see what
they used, did they appear old enough to have
experience and to know what they were doing?
Did the boiler keep the home warm as it was?
Did you buy a bigger boiler to cope with the addition?
Was the boiler running flat out in previous winters?
Or was it able to cope when running at medium
output, and had spare capacity to heat the addition?
Without knowing how high the ceiling is or how it was
built and how well it is insulated helping is a trifle
difficult.
A typical addition, of that size and of reasonable
specification would need 3 to 4 Kw./10,236 to 13,648 Btu to maintain a comfortable temperature.
Do you need a warm basement?
Was it explained how much heat is lost by heating a
basement, that you do not live in, and how much this
will cost you year after year and what impact this has
on heating the parts of the home you do use?
How much heat is lost from uninsulated pipes and
how this effects the radiators and the cost of heating
your home.
Who decided that the heat output from the radiators
could cope with the amount of insulation fitted in the
walls and floor in really cold weather.
You will end up with two choices.
To increase the heat input....and forever waste
money on heating that will get more expensive year
on year.
To seal all the holes in your home that let your warm
air out and cold air in and to improve the insulation.
This latter process will be a one off cost, that will
save you a fortune over the years.
#12
12-25-10, 10:18 AM
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Thank you Chandler. I have been in so many forums here, this site is great, can't believe it went under my radar for so long. Wish it was around back when we added that room.
Yes, the insulation is in between the floor joists. We filled all CS openings with canned spray foam insulations. I also closed vents with 2" thick pinkboard cut to fit and filled around edges/gaps with spray foam. Those steam pipes get pretty hot, so my thinking was if I could use a high r-value of insulation (my reason for liking polyiso) on block walls and cut off humidity coming thru walls & floor with 6 mil VB, the temp down there would be a little warmer and less of that chill that this would help with the above room.
The walls of my addition are 2x4 with fiberglass batting. I should point out the ceilings are 10.5 high except they slope down to 8" on both sides of room at about 5' before the wall. Also, lots of glass, 2-3x4ish skylights, 1 patio door, 2 double hung avg sized windows, 1 wood door with glass window, 3 outside walls one north facing. We are in NJ about 15 min from NYC. Summers are hot & humid, winters are usually 20 degree days from mid-dec thru to end of Mar. If I knew back when we did this what I know now, it would have gone very differently, but can't put the genie back in the bottle so to speak.
I also just thanks to this great site, have come to realize the radiators out there are way undersized. I took out the paperwork for my heater and calculated that we can handle more than we are currently using. Am thinking of switching addition radiators with way-oversized upstairs BR radiators. (Post WWII home, heat was cheap and they way overcompensated). Problem is we need a lot of muscle to move these probably 300 lb cast iron obstacles. I do prefer to insulate as best I can in crawlspace and the rest of the home. We are also going to remove trim and outlets etc. and spray foam insulate where needed. Then we can consider radiator changes.I am going to poke around more at the heating forum.
TY Again!
HAPPY HOLIDAYS ALL!
Anne
Yes, the insulation is in between the floor joists. We filled all CS openings with canned spray foam insulations. I also closed vents with 2" thick pinkboard cut to fit and filled around edges/gaps with spray foam. Those steam pipes get pretty hot, so my thinking was if I could use a high r-value of insulation (my reason for liking polyiso) on block walls and cut off humidity coming thru walls & floor with 6 mil VB, the temp down there would be a little warmer and less of that chill that this would help with the above room.
The walls of my addition are 2x4 with fiberglass batting. I should point out the ceilings are 10.5 high except they slope down to 8" on both sides of room at about 5' before the wall. Also, lots of glass, 2-3x4ish skylights, 1 patio door, 2 double hung avg sized windows, 1 wood door with glass window, 3 outside walls one north facing. We are in NJ about 15 min from NYC. Summers are hot & humid, winters are usually 20 degree days from mid-dec thru to end of Mar. If I knew back when we did this what I know now, it would have gone very differently, but can't put the genie back in the bottle so to speak.
I also just thanks to this great site, have come to realize the radiators out there are way undersized. I took out the paperwork for my heater and calculated that we can handle more than we are currently using. Am thinking of switching addition radiators with way-oversized upstairs BR radiators. (Post WWII home, heat was cheap and they way overcompensated). Problem is we need a lot of muscle to move these probably 300 lb cast iron obstacles. I do prefer to insulate as best I can in crawlspace and the rest of the home. We are also going to remove trim and outlets etc. and spray foam insulate where needed. Then we can consider radiator changes.I am going to poke around more at the heating forum.
TY Again!
HAPPY HOLIDAYS ALL!
Anne
