Thought I would post this for the "non believers", "those in denial", but more importantly for those of you who I unfortunately see posting as living in a drafty "whatever", who think that more BTU's is the answer to all your heating woes. The last group can be helped, the first two are lost causes. Destined to forever live in the cold & complain about it. My apologies for the length of the post, details matter as I hope you will come to appreciate when you have time to digest this post & relate it to your own situation.
We finished a shop for a customer in Oct - Nov. Thought I would share with you some of the details of construction as well as the results in required heating of the building.
Size: 60'x40'x12' high walls. So 2400 sq ft of floor space & 28,880 cu ft of space in the structure.
Const type: concrete grade beam on concrete ribbon footing with 2" high density foam on inside face of grade beam.
: concrete slab on grade with 2" high density foam under entire floor.
: tubing in floor, 12 zones - 200 sq ft/zone.
: ext walls 2"x6"x16" O.C. 3/8" O.S.B. sheathing on exterior. Tyvek house wrap. Vinyl siding. R19 fiberglass. 6mil vapor barrier. 3/8" O.S.B.interior sheathing.
: Doors: one 16'x10' O.H. door, R20 foam core. Two 8'x10' O.H. doors, R20 foam core. Two man doors 36"x80", R20 foam core.
: Windows: Four 5'x5', R4.8 dual pane vinyl.
: Roof: 2"x4" engineered 4/12 pitch, high heel trusses 24" O.C. Fiberglass reinforced asphault shingles. 13" R50 blown in cellulose in attic.
There is nothing special about this type/method of construction, actually most of it is min code here. The customer let me know in advance that the budget was tight on this one, so nothing fancy please just good solid work. Christmas was coming soon & all that. As usual the devil is in the details. So here are some non minimum code details that matter.
On each plug, switch, fixture, etc in an insulated cavity I install a vapor barrier hat (standard code requirement here). On this job there were over 30 on both the interior face, exterior face, as well as the ceiling. When the walls are sheathed I foam them in so I gain back as much R value as possible. Having an R19 reduced to an R9 by installing a switch is not a loss I am willing to accept (you shouldn't either). We also foam all doors & windows as well as small gaps in the framing, no point trying to fit a 2" wide piece of 5 1/2" thick insulation in, easier & better to foam it. Also we NEVER twist, compact, pinch or otherwise force insulation in any cavity. It is called friction fit for a reason, it should always be 1/2" bigger than the space it is going into, no more no less. It is not called force it, crush it, shove it, kick it or I hate doing this so lets just get it in so I can do something else insulation. Vapor barrier deserves attention as well, we seals all penetrations/seams first with acoustic sealant then with const tape (red "tuck" tape here) helps keep the acoustical sealant out of electrical boxes etc. We never cover the vapor barrier until we are satisfied with the work. No half measures.
Long & short of it is after some (minor) attention to detail, we are satisfied with the quality of the job & the results they should yield. So job is done & we leave.
3 weeks later I receive a call from the customer about trouble he is having heating his shop. As I am driving out I have all sorts of hydronic problems racing through my head & I am preparing to try & trouble shoot them, turns out that those thoughts were a waste of my time, (it wasn't the hydronics at all).
The customer is already in the shop waiting for me to arrive, so I go in (I notice that it is cooler than I thought he would be keeping it) & I immediately think that OMG the high end mod/con boiler that I had recommended, install by the contractor I had recommended has failed (awful thought & remember hydronics were not the problem) so I ask what seems to be the problem? He points to a 750 watt electric heater he has running on the floor, smiles & states that he was able to keep the shop at 5-7 C (41-44.6 F) during the -30 -35 C (-22 -31 F) cold snap we had (it lasted 7 days). No other working source of heat in the shop, except for his daughters two bunnies 3-4lb each, that his wife had insisted that he rescue from a very hungry looking weasel.
So with the heat sources stated above he was able to achieve a 35-42 C (63-75.6 F) increase in temp (not bad at all).
Almost forgot: the trouble he said he was having heating his shop:, turned out to be that he could not justify to his wife installing a mod/con nat gas boiler in the new shop as he was sure the cost (electric) of operating the boiler, pumps, ZVs etc would exceed the cost of running the 750 watt electric heater.
On the upside he did get the OK from his wife to spend the 10K they had budgeted for the boiler & install on boy toys for his new shop.
Hope this helps some of you too see the "value of insulation". Not just how much you put in but how you put it in as well. Details matter.
We finished a shop for a customer in Oct - Nov. Thought I would share with you some of the details of construction as well as the results in required heating of the building.
Size: 60'x40'x12' high walls. So 2400 sq ft of floor space & 28,880 cu ft of space in the structure.
Const type: concrete grade beam on concrete ribbon footing with 2" high density foam on inside face of grade beam.
: concrete slab on grade with 2" high density foam under entire floor.
: tubing in floor, 12 zones - 200 sq ft/zone.
: ext walls 2"x6"x16" O.C. 3/8" O.S.B. sheathing on exterior. Tyvek house wrap. Vinyl siding. R19 fiberglass. 6mil vapor barrier. 3/8" O.S.B.interior sheathing.
: Doors: one 16'x10' O.H. door, R20 foam core. Two 8'x10' O.H. doors, R20 foam core. Two man doors 36"x80", R20 foam core.
: Windows: Four 5'x5', R4.8 dual pane vinyl.
: Roof: 2"x4" engineered 4/12 pitch, high heel trusses 24" O.C. Fiberglass reinforced asphault shingles. 13" R50 blown in cellulose in attic.
There is nothing special about this type/method of construction, actually most of it is min code here. The customer let me know in advance that the budget was tight on this one, so nothing fancy please just good solid work. Christmas was coming soon & all that. As usual the devil is in the details. So here are some non minimum code details that matter.
On each plug, switch, fixture, etc in an insulated cavity I install a vapor barrier hat (standard code requirement here). On this job there were over 30 on both the interior face, exterior face, as well as the ceiling. When the walls are sheathed I foam them in so I gain back as much R value as possible. Having an R19 reduced to an R9 by installing a switch is not a loss I am willing to accept (you shouldn't either). We also foam all doors & windows as well as small gaps in the framing, no point trying to fit a 2" wide piece of 5 1/2" thick insulation in, easier & better to foam it. Also we NEVER twist, compact, pinch or otherwise force insulation in any cavity. It is called friction fit for a reason, it should always be 1/2" bigger than the space it is going into, no more no less. It is not called force it, crush it, shove it, kick it or I hate doing this so lets just get it in so I can do something else insulation. Vapor barrier deserves attention as well, we seals all penetrations/seams first with acoustic sealant then with const tape (red "tuck" tape here) helps keep the acoustical sealant out of electrical boxes etc. We never cover the vapor barrier until we are satisfied with the work. No half measures.
Long & short of it is after some (minor) attention to detail, we are satisfied with the quality of the job & the results they should yield. So job is done & we leave.
3 weeks later I receive a call from the customer about trouble he is having heating his shop. As I am driving out I have all sorts of hydronic problems racing through my head & I am preparing to try & trouble shoot them, turns out that those thoughts were a waste of my time, (it wasn't the hydronics at all).
The customer is already in the shop waiting for me to arrive, so I go in (I notice that it is cooler than I thought he would be keeping it) & I immediately think that OMG the high end mod/con boiler that I had recommended, install by the contractor I had recommended has failed (awful thought & remember hydronics were not the problem) so I ask what seems to be the problem? He points to a 750 watt electric heater he has running on the floor, smiles & states that he was able to keep the shop at 5-7 C (41-44.6 F) during the -30 -35 C (-22 -31 F) cold snap we had (it lasted 7 days). No other working source of heat in the shop, except for his daughters two bunnies 3-4lb each, that his wife had insisted that he rescue from a very hungry looking weasel.
So with the heat sources stated above he was able to achieve a 35-42 C (63-75.6 F) increase in temp (not bad at all).
Almost forgot: the trouble he said he was having heating his shop:, turned out to be that he could not justify to his wife installing a mod/con nat gas boiler in the new shop as he was sure the cost (electric) of operating the boiler, pumps, ZVs etc would exceed the cost of running the 750 watt electric heater.
On the upside he did get the OK from his wife to spend the 10K they had budgeted for the boiler & install on boy toys for his new shop.
Hope this helps some of you too see the "value of insulation". Not just how much you put in but how you put it in as well. Details matter.