Expert: Richard Taylor, AIA - 1/21/2010

Question
Is it advisable to build a small single story beach house using load bearing stone walls? Considering the extreme conditions in terms of sand, wind pressure and sometimes water waves hitting the front at high tides would a load bearing structure sustain for longer than a post and beam one?

Answer
Saira - thanks for your question.

At first glance, it would stand to reason that a massive structure would be less susceptible to damage in this situation than a wood structure.  After all, it's big and heavy, right?  But the forces at work on coastlines - and especially sandy beach sites - are far more complex than that.

Beach sites are unique because of soil conditions.  Whatever forces mother nature throws at a structure above ground (wind, water), it's ability to resist those forces is dependent upon the connection that it has with the ground.

Sand is a lousy soil type for building on because it doesn't compress well and because it is so easily eroded by water.  Regardless of the mass of a stone structure, it wouldn't take much water and wave action to shift the sand underneath it and destroy the house.

That's why we use pilings at the beach.  Pilings are wood poles driven deep into the sand - deep enough that they're not affected by wave action above.

And of course a stone structure would be build right at grade while a wood-framed structure on pilings can be built above grade, allowing high tides and moderate storm surges to pass underneath without causing damage.  The interior of your stone house would be ruined every time a storm passed by!

A properly-designed wood structure can "flex" with the wind, transferring the lateral loads into the ground through the pilings.  A stone structure will hold up to winds to a certain amount, then will suddenly fail completely.  Masonry isn't flexible and isn't intended to withstand strong lateral loads - especially on loose sandy soils.

Finally, a beach house of any construction type is going to suffer occasional damage, and will need repairs.  That's a lot easier and less expensive on a wood-framed structure than on a masonry one!

Hope this helps,

Richard Taylor, AIA
www.rtastudio.com
www.rtastudio.blogspot.com
www.rtaplans.com