Delayed wall warning

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I go the message:

custom weighting can not be calculated for SPACE EL1 Core Plnm (B.C43) has
0 delayed walls, 1 delayed floors and 0 delayed ceilings. There should be
at least a delayed wall and floor, a delayed wall and ceiling, or a delayed
ceiling and floor for custom weighting factors to be calculated. ASHRAE
weighting factors with floor weight of 70 lb/ft2 (342 kg/m2).

How can i fix this problem?

Thanks

Brian

Brian Lo's picture
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Joined: 2011-11-12
Reputation: 0

Direct solution: Define the constructions that space's surfaces
reference using layers that have mass. Entry with only U-value =
weightless.

Otherwise: I think this message is telling you eQuest can't figure out
how heavy the contents of the room (surfaces, furniture, etc...) are,
and is therefore assuming 70lb/ft2. You could just accept that
assumption if it's reasonable for your project.

~Nick

NICK CATON, P.E.

Nick-Caton's picture
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Joined: 2011-09-30
Reputation: 805

As the message states, if you want to calculate custom weighting factors, i.e.,
FLOOR-WEIGHT=0, you have to input enough of the space surfaces as delayed surfaces. It
looks like you're modeling the walls and ceiling as "quick" surfaces defined only by
R-value or conductance. You have to model them as delayed surfaces with thermal mass,
that means inputting them as LAYERS with material properties of thickness, conductance,
and specific-heat.

Joe

Joe Huang's picture
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Joined: 2011-09-30
Reputation: 406