Document Search

Wall assembly design and construction needs to consider rain, temperature, humidity as defined by the hygro-thermal regions, annual rainfall and the interior climate classes as environmental loads… Read More

Yes, we have done unvented conditioned attics before….but mostly with spray foam and rigid foam insulations.  But we do not have to use spray foam and rigid foam insulations.  You can use almost… Read More

An edited version of this Insight first appeared in the ASHRAE Journal.By Joseph W. Lstiburek, Ph.D., P.Eng., Fellow ASHRAE The issues with stucco are pretty well understood and we have discussed… Read More

It is pretty weird to dig a big hole and drop a building into it.  A one story house with a basement is really a two story house that you dropped into the ground burying one story.  Think about it…… Read More

Everyone is running around sealing the outside of buildings and the term “air barrier” has gone from obscurity to buzz word in less than a decade.  But if you look at the physics we are sealing the… Read More

…articulaciones* y esquinas y penetraciones...much more stylish…much more interesting than English.  The battle to control water entry is won at building joints and corners[1] not so much at… Read More

The problem with flood damaged buildings is that the damage is done by dirty water.  Everything imaginable and unimaginable is in flood water.  We call it “black water” or Category 3 water.  It… Read More

With the “perfect wall” we were here way back when (BSI-001: The Perfect Wall). The perfect wall has four control layers outside of the structure:a water control layeran air control layera vapor… Read More

Maybe not. For years I have said that dog won’t hunt1. I have come around. The engineer in me likes tools. I can’t help it – it is a genetic defect we engineers are born with. With therapy we… Read More

Sometimes the obvious is not so obvious. And sometimes the not so obvious becomes obvious. For example installing leaky ductwork1 in a vented attic is a pretty dumb idea (Figure 1). It leads to… Read More