Framing a roof with I-joists over the existing roof makes a ton of room for insulation and offers a short lesson in vapor movement through assemblies

Condensation is when moisture in the air hits a cool enough surface to convert the vapor into water.

Four ways to prevent ice dams in three types of roof, for two climates in one video. Boom.

Why insulating on top of a house is better than insulating inside

Hands-on training with local pros at the largest construction event in the Northeast

A big problem, for roofs in cold climates, but what causes it and how can you fix it?

A tight air barrier is the best way to build an energy-efficient house. Outside the sheathing are many chances to make it better.

A thermal break and solid backing puts the window on the outer face of a thick wall. Now, there's room on the inside window sill for cats and bowling trophies

Stack effect is relentless: it is always working, when you’re awake or asleep, even during blackouts. And it feeds on itself.

When air sealing a house, begin with the biggest holes and work toward the small ones

"In order to maximize the buildable area on the infill lot, we had to go fairly deep and do some extensive shoring."

—Dan Whitmore of Hammer & Hand 

Offset the joints and seal the gaps to keep air leaks out of the thick walls

This is the first episode of 7 Minutes of BS (building science). We break it down with engineers and building scientists.

What the HERS index is and how to make it work for you

Windows cannot rest on the foam, so they hang from wood bucks

Direct the heat toward the feet

Letting the brick dry evenly is the key for old masonry walls that want to leak less energy

Dr. Bailes does the math