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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

Vitruvius had it right 2,000 years ago: “…if a wall is in a state of dampness all over, construct a second thin wall a little way from it…at a distance suited to the circumstances…with vents to the… Read More

“What we’ve got here is failure to communicate . . .”1In what is turning out to be an unfortunate turn of phrase the terms “unvented attics” and “unvented roofs” have entered the lexicon. A lot of… Read More

We live at the bottom of an ocean of air. Each of us is carrying around 14.7 pounds per square inch when at the beach in Miami1. We are powerful creatures indeed. Imagine carrying around 101,000… Read More

Putting ductwork outside is bad enough, but putting ductwork in an attic is even worse (Photograph 1). Attics are even hotter than outside during the summer and as cold as the outside in the winter.… Read More

Life was simple when I grew up in Canada. Winters were long and cold, we had no air conditioning, walls dried to both the outside and the inside and the Toronto Maple Leafs would win Stanley Cups.… Read More

When Mother Nature came up with wood it gave it magical properties that try as we might we mere humans find it difficult to improve upon or to transfer to other materials we come up with.1 One of… Read More

If you take rocks and melt them and blow air through them you get fluffy rocks. And fluffy rocks don’t burn. If you take gypsum and make it into sheets you get “sheet rock”. And guess what? Rocks don… Read More