Contact

We read every message and usually reply within two business days.

Corrections

If a figure or formula on one of our pages looks wrong, tell us the page and what you found, ideally with a link to the source. We check it and update the page.

What we can't help with

Advice on your building. We can't assess your roof, slab or wall, or say whether a design is safe. Ask a licensed contractor, an engineer or your local building department.
Contractor recommendations. We don't recommend or match you with contractors.

We never ask for passwords or payment details. If someone claiming to be us does, it's a scam.