Advice on Historic Preservation Project

[PatBethea]

There's a small town nearby (I'm in Florida) that is refurbishing an old train depot with funds from a historic preservation grant. Originally they didn't think they would have enough money to install any mechanical systems, but as the end of the project is nearing, they have decided that there is enough to do "something".

I met the architect/grant administrator at the site this afternoon to consult on the project. I didn't measure the building (and I haven't seen any drawings yet), but I'd say its roughly 30' wide x 80' long. Approximately half of the depot is an old wooden structure and the other half is concrete block. The wooden half of the building is going to contain a couple of offices for the city. The other half is to be used as some sort of museum. The office area is very straight-forward - the windows are being replaced and proper insulation is being installed. I'll simply use a heat pump to take care of the heating/cooling in this section.

The museum portion is a bit problematic. The walls will be bare concrete (no insulation). There are two large (~8-10' wide), sliding barn-type doors. The floor is tongue and groove flooring over a crawl space. Then there's the roof - they want the old timber rafters and planking to remain visible. Loose fitting planks sit atop the rafters. Roofing felt and metal decking are sitting on top of the planking.

Because there is no insulation and this section is going to leak like a sieve, I recommended against placing an A/C unit in this area. I recommended that simple ventilaion be provided. However, because this area is to be used as some sort of museum, I'm concerned about humidity. Can anyone suggest any other options to explore?

 

[marcoh]

Depends on the budget and energy requirements. Might be feasible to somehow incorporate a full outside air system with displacement ventilation and talk about tempering rather than temperature control?

 

[PatBethea]

Thanks, Marcoh - budget constraints are pretty tight - both installation and operation.

Right now I'm thinking about maybe oversizing the system for the office area by a ton and ducting the "overflow" into the museum area to do just that - offer a little tempering.

 

[GMcD]

Why air condition at all? Historically that building didn't have air conditioning before, so why would it "need" it now? Depending on your climate zone I'd be inclined to go as passive/low-tech as possible with an HRV/ERV ventilator with maybe an evaporative cooling section (DesChamps) and avoid the whole mechanical cooling approach. If a displacement ventilation system isn't feasible- consider some panel nozzle diffusers to allow occupants to use locally controlled air velocity as a cooling effect- check these: Seiho spotpaks:

http://www.seiho.com/product/pkp/pkp.html

 

[PatBethea]

GMcD,

I'm in Florida - very humid. Seeing how a museum is desired, some sort of humidty control seems in order. Thanks for the link - I need to closer look at those a little later.

 

[quark]

You can get good advice from Munter's dehumidification handbook. If I recall correctly, they have a chapter and worked out examples for humidity control in museums.