Hi All,
Compliance with this credit in fully ducted return systems has been straight forward, however, the LEED Reference Guide is not too clear on how exactly open plenum return systems are to be addressed. The Reference Guide states that "If an unducted plenum over the construction zone must be used, the team should isolate it by having all ceiling tiles in place". It is not clear if the MERV 8 filtration media should be installed at the return air grilles, or at the return duct mains to the air handling unit. It seems that placing the MERV 8 filters at each RA grille may not be the best solution, as the plenum will still accumulate dust during construction and during occupancy. It seems that the more prudent and cost effective solution would be to place MERV 8 filtration media at the return air mains to each air handling unit. Does anyone have experience with this? Thanks!
Dylan Connelly
Mechanical EngineerIntegral Group
LEEDuser Expert
472 thumbs up
March 20, 2013 - 7:55 pm
Naten,
MERV 8 filtration media at the RA mains has been sufficient on all of our projects with plenum return.
Erik Ruoff
PrincipalThe Green Engineer, Inc
36 thumbs up
March 21, 2014 - 10:06 am
FYI - Following is text from LEED Interpretation ID#2143, “providing MERV 8 filtration at the return duct risers is acceptable provided the ceiling tiles and return grilles have not been installed. Once the ceiling and return grilles are in place, MERV 8 filtration media must be shifted to the return grilles (or other openings in the plenum) if the air handling units are to be used during construction.”
John Albrecht
AIA, LEED FellowChicagoGreen
4 thumbs up
January 21, 2015 - 11:27 am
If the above project were also pursuing IEQc5, is it correct to assume that "MERV 13" filters should be installed in lieu of the MERV 8 filters mentioned above? Just checking, and thanks again LEEDuser!
Dave Hubka
Practice Leader - SustainabilityEUA
LEEDuser Expert
534 thumbs up
January 21, 2015 - 11:57 am
Hi John,
If EQc5 is pursued you are only required to install MERV 8 filters at the returns.
Dave.
Michelle Halle Stern
Senior Sustainability ConsultantGreenwood Consulting Group
121 thumbs up
January 21, 2015 - 12:52 pm
The MERV 8 filters are fine during construction, but need to be replaced with MERV 13 filters before occupancy for EQc5.