Hello,
I have two questions:
1) We have a residential multi-unit project with approximately 100 units. All the individual units are naturally ventilated with openable windows. (ie. no HVAC ventilation system) What are the ETS requirements in this case? Will sealing the exterior doors of the units and prohibit smoking in the corridors suffice the requirements?
2) I do not understand the blower door test requirement. The blower door test is usually done to find the leakage rate of a unit for energy efficiency purposes. Typically the test equipment is installed on the exterior door blowing air into the residential unit to find leakage points on the exterior walls and windows. In testing for the ETS, my understanding is that we would like to prevent leakage to the corridors so the test equipment cannot be installed on the exterior door. Then it would make sense to install it in one of the interior doors blowing air into the zone that has the exterior door... But what if the corridor is pressurized and we have not installed door sweeps for ventilation purposes. In that case the blower door test will fail... So this is quite confusing. Can anyone help? Where should we install the blower door test equipment and to measure what exactly?
Thanks.
David Posada
Integrated Design & LEED SpecialistSERA Architects
LEEDuser Expert
1980 thumbs up
August 11, 2011 - 12:29 pm
Re: 1) Unless smoking is prohibited in the whole building, which some rental properties have done, each unit is considered a "smoking room" and has to meet the credit requirements for door sweeps, sealing of plumbing, HVAC, and electrical penetrations in the walls, dedicated direct exhaust for each unit and verification with blower door testing.
Yes, prohibiting smoking in all common areas will comply if smoking is also prohibited on any exterior balconies or decks that are w/in 25' of an operable window or intake vent, which is probably true of most exterior decks.
2) The blower door test is to verify that smoke will not migrate from unit to unit -which can certainly happen. This can be challenging to prevent, especially in metal stud framed construction. For party walls between units, make sure electrical outlets and other penetrations don't share a stud cavity or other chase that allows air to move between units. Extra effort may be needed to instruct and supervise that sub contractors and installers are providing adequate air sealing at all penetrations, fixtures, etc. Pocket doors can be problematic; gaskets may be needed on fixture, outlet and switch covers, etc.
In our experience, the blower door has usually been set up at the unit entry door. I believe it's acceptable to cover with plastic & tape the exterior windows and kitchen & bath vent fans since these are connected to the outside and not to other units, but you'll want to verify that. The test is thus determining the air leakage in and out of the unit through the boundary it shares with other units, which is a good indicator of ETS transmission between units.
Hope that helps!