PDA

View Full Version : hvac guys - school me


shaun y
2012-02-07, 07:37 PM
for starters my house is 90 years old. i live in the mbr upstairs and it is essentially a "loft." probably 80% of my ceiling is the roof of the house, with nothing but drywall and fiberglass separating me from the elements.

here is the thing: there are basicially 2 vents in my room (another in the bathroom that is behind a closed door) and the room is probably 600-800sq ft total. in order to keep the downstairs mainfloor at 68 degrees, my room gets HOT. i have black shingles on the house and notice the problem mostly when it is sunny out, even if it is only 20 degrees outside i can feel the difference in heat vs. when it is cloudy. the main floor is all hardwood floors and there are plenty of windows, so i don't know if that's where heat keeps escaping causing the furnace to run longer, but i have a coat room inside my front door so i essentially have two front doors worth of insulation, and half the windows on the main floor are newer, so i don't know how it can "leak" heat so bad. what can i do to keep my bedroom from overheating outside of taping cardboard to the vents in my room?

this is a very nice house, my mom paid $180k for it two years ago and i moved in after she moved to san diego. i plan to buy it from her when she is legally allowed to sell (can't yet due to stipulations with the first-time homeowner tax credit she used) and i want to live here for a long time, so i am looking for a quality solution.

thanks in advance.

black797
2012-02-08, 09:46 AM
Insulation.

Insulate between floors and insulate the space between drywall and roof.
How many windows are on your 2nd floor? They make a film/screen for your windows that pulls in and traps heat in the winter and when you flip it in the summer it reflects the heat.
Check your ducting and put tape around any gaps or holes.
Open all vents on the 1st floor in the winter and close them in the 2nd floor. Opposite in the summer. Heat rises, cool air falls. I've noticed a big difference doing this in my house.

acvw_insanity
2012-02-08, 11:15 AM
Insulation 101:

Make sure you have adequate insulation in your roof (as stated before) I think industry standard is like r29 now or greater. Since you have minimal space, this might be an issue. How is your roof vented? And how are your soffit vents? Because it still needs some space to move air. Also, when it snowed, did the snow stay on your roof? or did it melt? Black shingles or not, if your attic/top floor cieling insulation is good enough, you wont get heat loss to the initial ceiling, and the snow will stay on your roof(which means you are not experiencing heat loss)
Make sure yourhvac pipes, vents are sealed and tight, and your furnace filter is clean. Also, what most people dont realize is that the metal work benefit the registers are installed quickly and can still leak warm air into the walls.
Make sure your weather stripping on all exterior doors, and thresholds are in good shape. Also, make sure all exterior windows are sealed, even use plastic to seal them from drafts in the winter months.



Buy a infrared temp gauge from menards or lowes, go around and take random temps on walls, windows, ceilings, etc and see if you are experiencing cold spots, etc.


Also, you mention new windows. New windows can still be crap. What type of windows are they? I lived in a duplex that had "new windows" and they were aluminum, single pane, uninsulated windows that sucked. They were so drafty and inefficent that they were worthless.


Or, I could come over and check out your house. I'm buy no means a certified HVAC guy, but I have plenty of experience with this stuff, and know how to do spray in insulation, batt insulation, and have always made sure where I lived has been in good shape. I bet your house is leaking bigtime on your main floor. It's common in older homes, unless the owner has made sure that the insulation and hvac have been kept up. Also, do you have a basement?

shaun y
2012-02-08, 11:48 AM
Insulation.

Insulate between floors and insulate the space between drywall and roof.
How many windows are on your 2nd floor? They make a film/screen for your windows that pulls in and traps heat in the winter and when you flip it in the summer it reflects the heat.
Check your ducting and put tape around any gaps or holes.
Open all vents on the 1st floor in the winter and close them in the 2nd floor. Opposite in the summer. Heat rises, cool air falls. I've noticed a big difference doing this in my house.

i have 3 windows on the second floor and about 12 on the main floor. i will have to check ducts where i can. the house is old and so the upstairs vents don't close, they are just iron mesh, and they are huge so idk if lowes or home depot would cover vents to replace them that are that size that can close.

insulation is might be what it comes down to but i can see that being a $10k project (pulling numbers out of my ass).

Insulation 101:

Make sure you have adequate insulation in your roof (as stated before) I think industry standard is like r29 now or greater. Since you have minimal space, this might be an issue. How is your roof vented? And how are your soffit vents? Because it still needs some space to move air. Also, when it snowed, did the snow stay on your roof? or did it melt? Black shingles or not, if your attic/top floor cieling insulation is good enough, you wont get heat loss to the initial ceiling, and the snow will stay on your roof(which means you are not experiencing heat loss)
Make sure yourhvac pipes, vents are sealed and tight, and your furnace filter is clean. Also, what most people dont realize is that the metal work benefit the registers are installed quickly and can still leak warm air into the walls.
Make sure your weather stripping on all exterior doors, and thresholds are in good shape. Also, make sure all exterior windows are sealed, even use plastic to seal them from drafts in the winter months.



Buy a infrared temp gauge from menards or lowes, go around and take random temps on walls, windows, ceilings, etc and see if you are experiencing cold spots, etc.


Also, you mention new windows. New windows can still be crap. What type of windows are they? I lived in a duplex that had "new windows" and they were aluminum, single pane, uninsulated windows that sucked. They were so drafty and inefficent that they were worthless.


Or, I could come over and check out your house. I'm buy no means a certified HVAC guy, but I have plenty of experience with this stuff, and know how to do spray in insulation, batt insulation, and have always made sure where I lived has been in good shape. I bet your house is leaking bigtime on your main floor. It's common in older homes, unless the owner has made sure that the insulation and hvac have been kept up. Also, do you have a basement?

the snow melted off that first warm day on the side facing the sun, but i have a steep pitched roof so idk how much melted vs fell off. most all of the snow is still there on the shady side.

the windows are not super nice but i have never felt a really noticeable draft from any of them and the furnace doesnt run all day to heat the main floor to 68, i think the real problem is just an unproportional amount of heat gets blown up to the top floor vs the bigger 2nd floor, at least that's how it seems.

acvw_insanity
2012-02-08, 11:58 AM
the windows are not super nice but i have never felt a really noticeable draft from any of them and the furnace doesnt run all day to heat the main floor to 68, i think the real problem is just an unproportional amount of heat gets blown up to the top floor vs the bigger 2nd floor, at least that's how it seems.

Makes sense.


Well, if you have that many windows on your main floor and heat is still rising, then it goes to show that your not losing your heat out of your main floor windows.

black797
2012-02-08, 12:07 PM
Do you have a boiler or forced air system? You may be able to close off the ducting to the upstairs by the furnace. We have that option on some of our pipes. It may be cheaper to install that option in the basement than buying new vents for all rooms.

shaun y
2012-02-08, 12:12 PM
Do you have a boiler or forced air system? You may be able to close off the ducting to the upstairs by the furnace. We have that option on some of our pipes. It may be cheaper to install that option in the basement than buying new vents for all rooms.

i have forced air. i will have to check that, i didn't know there might be a way in the basement to close the upstairs vents. ossum :)

acvw_insanity
2012-02-08, 12:38 PM
i have forced air. i will have to check that, i didn't know there might be a way in the basement to close the upstairs vents. ossum :)

You will just have to track down the HVAC ducting to the main stack.

DIYAutoRepair
2012-02-08, 09:09 PM
for starters my house is 90 years old. i live in the mbr upstairs and it is essentially a "loft." probably 80% of my ceiling is the roof of the house, with nothing but drywall and fiberglass separating me from the elements.

here is the thing: there are basicially 2 vents in my room (another in the bathroom that is behind a closed door) and the room is probably 600-800sq ft total. in order to keep the downstairs mainfloor at 68 degrees, my room gets HOT. i have black shingles on the house and notice the problem mostly when it is sunny out, even if it is only 20 degrees outside i can feel the difference in heat vs. when it is cloudy. the main floor is all hardwood floors and there are plenty of windows, so i don't know if that's where heat keeps escaping causing the furnace to run longer, but i have a coat room inside my front door so i essentially have two front doors worth of insulation, and half the windows on the main floor are newer, so i don't know how it can "leak" heat so bad. what can i do to keep my bedroom from overheating outside of taping cardboard to the vents in my room?

thanks in advance.


From your post, I gather your main problem is cooling your room/loft.

1. Being 90yo, you probably don't have much insulation in your roof. If it was insulated during a remodel at some point maybe it's better. You can add or reinsulate but that will require you to pull down all the drywall.

2. It's a loft, all the heat in your house will rise up to your room, nothing you can really do about it. You can seal off your room as best you can and maybe insulate your interior walls.

3. If you could find a way to recirculate the warm air from up top to down below that would help. To me "loft" means that your room is open to the main floor below. Maybe you can install a ceiling fan to help push the warm air down to the main floor.

shaun y
2012-02-08, 09:25 PM
Sorry. It's not open to the main floor but it covers the entire width /depth of the hous, the stairs are all inside my room and the windows sit low on the wall so it feels like a lift to me. I knew it's been remodeled at some point because most of the walls are drywall not plaster.

chiggy
2012-02-09, 12:55 AM
everyone has been saying insulation and they aren't wrong. I just wanted to throw out there that there is a newer insulation material and technique that sounds like it's exactly what you need. I'm afraid I don't know the exact brand name but it's a foil backed, very thin, polyethylene foam, type of stuff that is a great barrier for hot and cold. it does in 1 inch what other standard types of insulation does in 12 inches because of the reflective properties of it's foil layers. I want to call it prodex but I'm not sure if that's exact thing. I bet the fix for your situation is not going to be cheap since it might involve tearing down your ceiling and putting this stuff on the back of the plywood that your roof shingles are nailed to and then re-doing the ceiling. Over a decade or so it will pay for itself in heating and cooling costs. not to mention the comfort aspect.

black797
2012-02-09, 10:10 AM
everyone has been saying insulation and they aren't wrong. I just wanted to throw out there that there is a newer insulation material and technique that sounds like it's exactly what you need. I'm afraid I don't know the exact brand name but it's a foil backed, very thin, polyethylene foam, type of stuff that is a great barrier for hot and cold. it does in 1 inch what other standard types of insulation does in 12 inches because of the reflective properties of it's foil layers. I want to call it prodex but I'm not sure if that's exact thing. I bet the fix for your situation is not going to be cheap since it might involve tearing down your ceiling and putting this stuff on the back of the plywood that your roof shingles are nailed to and then re-doing the ceiling. Over a decade or so it will pay for itself in heating and cooling costs. not to mention the comfort aspect.


Or he could just do blown in insulation that will be a cheaper solution and give an R15 value.