How would you size

[Deleted User]

I have a fun project I am working on but I am not sure how to size a room say 20'x20'for it's heat requirments. This is a historic inn in Big Sur that is built out of 3/4" thick redwood siding only. There is no insulation anywhere and the structure can not be modifyed due to historic value. I have been given the go to heat the whole place using a hydronic system to deliver hot water heat to 7 rooms in one building and 5 rooms in another building as well as making hot water for domestic use. I have a great space to build a mec room and I was going to use 2 munckin with a P/S Loops. The question is how much BTU do I need. Thanks for your ideas, Mike

Gary Fereday

it is easy

On the pipe on the left side of this, "click on 'Free Heat Loss Calcs' " and follow instructions.
bigugh

steve_6

heat loss

download the free heat loss calcs. on this website

Mike T., Swampeast MO

Can't say how many BTUs

given the information but 3/4" redwood will have an r-value of about 1.0 A 2x4 on the "flat" will have an r-value of about 2.0 If studs are on 24" centers (I believe typical of single-wall construction) your total r-value for the walls should be around 1.25

Unless there is an intact, well-installed air barrier (like tar paper or sisalkraft) would guess that infiltration is somewhere between "poor" and "terrible" based on its wind exposure.

Probably a number of fireplaces so make certain you account for these in your heat loss calculation. "General" wisdom states that an open fireplace is a net heat loss even when operating. Exception could possibly be made for a fireplace with a MASSIVE stone chimney under CONTINUOUS operation but I have no idea how to compute its net gain to a structure with another form of heat--if any.