Glossary

I-beam: A type of load bearing beam made of metal or composite wood whose cross section is shaped like the letter I. Used for wide open spans.

Insulation: Any material that offers resistance to heat transmission. When insulation is placed in walls, ceilings or floors it reduces the loss or gain of heat from outside sources.  Fiberglass and wool are usually what the products of choice.

Interlocking shingles: Individual shingles that mechanically fasten to each other to provide wind resistance.