3 ms·

A triple decker that has its stud bays dense packed with cellulose, 3 inches of continuous exterior rock wool insulation, and fiber cement siding is pretty damn

by hx87 10y ago

A triple decker that has its stud bays dense packed with cellulose, 3 inches of continuous exterior rock wool insulation, and fiber cement siding is pretty damn fire resistant, even with <6 foot separation. Getting rid of exterior-facing wood and empty stud bays, which are fantastic heat pipes and chimneys, the flammability goes way down.

hga 10y ago
Especially since stud bays in those days were often continuous, they used available back then very long pieces of wood to frame the entire building, instead of stacking floors on top of each other: https://en.wikipedia.org/wiki/Framing_(construction)#Balloon_framing https://en.wikipedia.org/wiki/Framing_(construction)#Balloon... Yeah, I can see that, most likely long enough to give the fire department plenty of time to save the adjacent buildings, as I witnessed once (but didn't know their construction details). I worry about flat roofs, though, how fire resistant do they tend to be? Original formula asphalt shingle with an organic base aren't super fire resistant from what I've just read and basic principles (when I re-roof, which will require taking off 3 layers (!) plus the original wood shingles, I'll be sure to get the more fire resistant fiberglass base ones).
- hx87 10y ago
  If you're taking shingles, chances are you don't have a true flat roof (or just a terribly built one), since those are supposed to continuous roofing in order to withstand water puddles. Back in the day the only material available was asphalt tar, which obviously isn't very fireproof. Modern alternatives such as EPDM and TPO though are plenty fireproof, especially if placed on top of polyisocyanurate insulation (which doesn't burn, only char) instead of directly on the wood deck.
  - hga 10y ago
    Sorry for my lack of clarity, I was talking about both types of roofs, since the classic Somerville triple decker has a flat roof, and the classic Philadelphia a pitched roof with shingles. I was wondering about the former since I've never seen one as such, aside from some one story commercial ones when I lived in a higher adjacent apartment. And thanks for the comments, you've saved me some research when it comes time to replace my roof.
amluto 10y ago
Having lived in Somerville, there's another reason to eliminate empty stud bays: holy crap it's cold. We spent something like $200/month heating under 1000 sq. ft. to 62 degrees F in the winter for four hours a day. Take a wildly inefficient boiler, uninsulated steam pipes, crappy radiators next to exterior walls, and no insulation, and you get a hot basement, a freezing apartment, and insane natural gas use. I would love to see a law that requires landlords to get a basic energy audit and advertise the estimated heating cost. Then they'd have an incentive to fix it, which, quite frankly, is cheap: just blow dense-filled cellulose into the stud bays, insulate the pipes in the basement, and upgrade the boiler. At, say, $15k per unit, it'll pay for itself in a few years of tenants who want to heat to 68F for more than four hours per day. (Amusingly, my place had new double-paned windows. They were invariably warmer than the plaster walls in the winter.)
- markvdb 10y ago
  EU wide base regulation: https://en.wikipedia.org/wiki/Directive_on_the_energy_performance_of_buildings https://en.wikipedia.org/wiki/Directive_on_the_energy_perfor... In the UK: https://en.wikipedia.org/wiki/Energy_Performance_Certificate https://en.wikipedia.org/wiki/Energy_Performance_Certificate In Belgium: https://nl.wikipedia.org/wiki/Energieprestatiecertificaat https://nl.wikipedia.org/wiki/Energieprestatiecertificaat (nl language only, sorry) In Ireland: https://en.wikipedia.org/wiki/Building_energy_rating https://en.wikipedia.org/wiki/Building_energy_rating
- hx87 10y ago
  Landlords already have an incentive to make their units more energy efficient--they can capture the revenue stream that currently goes to the gas, electric, and oil companies. I'm not sure why more landlords don't do this though. Probably because methods that don't disturb tenants (e.g. exterior rock wool or foam insulation) run afoul of zoning/setback/property tax assessment rules, and those that do comply (e.g double stud wall retrofits) disturb the tenants and/or reduce marketable space.

by hx87 10y ago

hga 10y ago

Especially since stud bays in those days were often continuous, they used available back then very long pieces of wood to frame the entire building, instead of stacking floors on top of each other: https://en.wikipedia.org/wiki/Framing_(construction)#Balloon_framing https://en.wikipedia.org/wiki/Framing_(construction)#Balloon... Yeah, I can see that, most likely long enough to give the fire department plenty of time to save the adjacent buildings, as I witnessed once (but didn't know their construction details). I worry about flat roofs, though, how fire resistant do they tend to be? Original formula asphalt shingle with an organic base aren't super fire resistant from what I've just read and basic principles (when I re-roof, which will require taking off 3 layers (!) plus the original wood shingles, I'll be sure to get the more fire resistant fiberglass base ones).

hx87 10y ago
If you're taking shingles, chances are you don't have a true flat roof (or just a terribly built one), since those are supposed to continuous roofing in order to withstand water puddles. Back in the day the only material available was asphalt tar, which obviously isn't very fireproof. Modern alternatives such as EPDM and TPO though are plenty fireproof, especially if placed on top of polyisocyanurate insulation (which doesn't burn, only char) instead of directly on the wood deck.
- hga 10y ago
  Sorry for my lack of clarity, I was talking about both types of roofs, since the classic Somerville triple decker has a flat roof, and the classic Philadelphia a pitched roof with shingles. I was wondering about the former since I've never seen one as such, aside from some one story commercial ones when I lived in a higher adjacent apartment. And thanks for the comments, you've saved me some research when it comes time to replace my roof.

amluto 10y ago

Having lived in Somerville, there's another reason to eliminate empty stud bays: holy crap it's cold. We spent something like $200/month heating under 1000 sq. ft. to 62 degrees F in the winter for four hours a day. Take a wildly inefficient boiler, uninsulated steam pipes, crappy radiators next to exterior walls, and no insulation, and you get a hot basement, a freezing apartment, and insane natural gas use. I would love to see a law that requires landlords to get a basic energy audit and advertise the estimated heating cost. Then they'd have an incentive to fix it, which, quite frankly, is cheap: just blow dense-filled cellulose into the stud bays, insulate the pipes in the basement, and upgrade the boiler. At, say, $15k per unit, it'll pay for itself in a few years of tenants who want to heat to 68F for more than four hours per day. (Amusingly, my place had new double-paned windows. They were invariably warmer than the plaster walls in the winter.)

markvdb 10y ago
EU wide base regulation: https://en.wikipedia.org/wiki/Directive_on_the_energy_performance_of_buildings https://en.wikipedia.org/wiki/Directive_on_the_energy_perfor... In the UK: https://en.wikipedia.org/wiki/Energy_Performance_Certificate https://en.wikipedia.org/wiki/Energy_Performance_Certificate In Belgium: https://nl.wikipedia.org/wiki/Energieprestatiecertificaat https://nl.wikipedia.org/wiki/Energieprestatiecertificaat (nl language only, sorry) In Ireland: https://en.wikipedia.org/wiki/Building_energy_rating https://en.wikipedia.org/wiki/Building_energy_rating
hx87 10y ago
Landlords already have an incentive to make their units more energy efficient--they can capture the revenue stream that currently goes to the gas, electric, and oil companies. I'm not sure why more landlords don't do this though. Probably because methods that don't disturb tenants (e.g. exterior rock wool or foam insulation) run afoul of zoning/setback/property tax assessment rules, and those that do comply (e.g double stud wall retrofits) disturb the tenants and/or reduce marketable space.