What size you ask? I dunno, maybe 3br, 3ba, 2500 sq. ft. Is that pretty average?
A commercial on the tube says that, in the tropics, termites can eat 1000lbs of wood in a year. A friend told me (many years ago) that it actually takes a long time for termites to do large damage to a house, and he worked for the pest control company with the big bugs on their trucks. He knows a lot about bugs, and we wasted (hehe, wasted) many evenings talking about vermin and the pest business.
Did you know they sometimes look for termites using stethescope-like devices? You can hear the little rascals gnawing on your crib. Cool, huh.
Peace,
mangeorge
Enough to kill a witch.
Haha! 
40 tons for an 1800 sq. ft. townhouse with 3 BR, 2 bath plus a two-car garage.
I don’t know how to interpret the “1000lbs” figure. Is that per nest, per termite (nah), or what?
Living as I do in a wooden house in a termite infested area, I know that termites can eat most of the wood supporting a single wall of my house in about 6 months. I don’t want to talk about how I know this.
Termite species differ tremendously in the rate they eat houses, also.
I don’t know how much they weigh, but I’ll bet that I can jump higher than one.
Interesting question. I pondered this myself as I carted about 150 housebricks into my back garden, plus several 25kg bags of sand and cement, when I built a barbecue a couple of years ago. That was heavy, just to build a structure that would fit inside a 4ft cube. So how much does a whole house weigh? Maybe I’ll do some back-of-envelope calculations when I get a minute.
PS. Termites don’t eat brick. But we don’t get termites here. So why make houses out of termite food in termite zones, but not in non-termite zones? Don’t answer that one…
Google figures for the weight of a housebrick suggest 3-4kg. I’ll call it 4kg including the associated mortar for each brick.
The face area including the mortar is 240mm x 86mm, or 0.02m[sup]2[/sup].
Now, for ease of calculation, picturing a small semi-detached house as a cube 10m on each side, with double-leaf brick walls. That’s 8 walls each of 100m[sup]2[/sup], or 5000 bricks.
So that’s 40,000 bricks x 4kg = 160 tonnes just for the walls. No idea how much the roof would weigh, but I guess you could call it 200 tonnes for the basic shell of the house, without the foundations or any internal structure.