The building that I'm interested in is located in Daly City, CA. While it is very close to San Francisco (less than 10 miles/16 km), Daly City has a microclimate that can be quite different from that experienced in SF. In particular, Daly City can experience heavy fog lasting for almost an entire day.
I am curious what thoughts the WUFI community has regarding how heavy, consistent fog might affect simulation results. I'm currently considering purchasing METEONORM to generate usable climate data for Daly City, unless the prevailing opinion is that the presence of fog won't significantly affect the results.
Impact of heavy fog
Re: Impact of heavy fog
Dear Mr. Barratt,
there is probably no general answer to which degree consistent fog will affect the hygrothermal performance of building constructions. Robust constructions will probably not be affected, constructions with little performance reserves might possibly fail. If you suspect possible problems, it's certainly better to make sure that the higher moisture load that may be vented into the construction or the lower drying potential due to reduced solar radiation are not asking too much of the construction.
I had a look a the METEONORM database, but they have no data measured at Daly City. The closest stations with measured data are San Francisco, Berkeley, Oakland, Hayward Air Term., San Carlos Airport and Palo Alto Airport. So weather data for Daly City would have to be generated by interpolating between the closest of these stations, but I doubt that this would result in the particular microclimate you want. Specifying it as a location close to the sea would apparently only affect the interpolation of wind and temperature; the keyword 'fog' doesn't seem to appear in the documentation. So if you intend to use METEONORM, you should first contact its producers about whether it can do what you want.
If rain is of no concern for your construction, you may be able to find representative EnergyPlus weather files *.EPW (either for Daly City itself or for a suitable Californian climate zone). The new WUFI 4.2 (due out hopefully in one or two weeks) can read these files, or they could be converted to one of the other file formats WUFI can read.
Regards,
Thomas
there is probably no general answer to which degree consistent fog will affect the hygrothermal performance of building constructions. Robust constructions will probably not be affected, constructions with little performance reserves might possibly fail. If you suspect possible problems, it's certainly better to make sure that the higher moisture load that may be vented into the construction or the lower drying potential due to reduced solar radiation are not asking too much of the construction.
I had a look a the METEONORM database, but they have no data measured at Daly City. The closest stations with measured data are San Francisco, Berkeley, Oakland, Hayward Air Term., San Carlos Airport and Palo Alto Airport. So weather data for Daly City would have to be generated by interpolating between the closest of these stations, but I doubt that this would result in the particular microclimate you want. Specifying it as a location close to the sea would apparently only affect the interpolation of wind and temperature; the keyword 'fog' doesn't seem to appear in the documentation. So if you intend to use METEONORM, you should first contact its producers about whether it can do what you want.
If rain is of no concern for your construction, you may be able to find representative EnergyPlus weather files *.EPW (either for Daly City itself or for a suitable Californian climate zone). The new WUFI 4.2 (due out hopefully in one or two weeks) can read these files, or they could be converted to one of the other file formats WUFI can read.
Regards,
Thomas