ArcaMax

If you’re planning to replace an old and rotted window sill with a glass block unit, it’s a good idea. If it’s the window above a bathtub in an older home, it often succumbs to exposure to moisture, and the sill and wooden frame rot away. Replacing the window with a glass block unit is a good solution because it allows light in from the outside while providing privacy inside. The replacement unit is an all-in-one pre-constructed glass block window framed into easy-to-install vinyl jambs and comes in dozens of standard sizes. You’ll find them where building materials are sold at lumber yards and home centers.

While this used to be a job for a pro, a handy homeowner with carpentry experience and tools can do the job. It involves removing the old window, sizing the rough opening to the proper dimensions, fastening the block window in place, and reinstalling interior and exterior trim. And most of the work is done from the interior side of the wall. This job can be more complicated and difficult if you're installing the window in the second floor of a house, because working on a ladder and manhandling the window unit takes more than ordinary skills. You'll also need a helper to muscle the unit in place.

If you have any doubts about doing it yourself, hire a contractor who will charge $612, which includes labor and material, to install a new 32-inch-by-24-inch glass block window unit. If you have carpentry experience, you can buy the unit for $285, install it, and pocket a 53% saving. Plan to budget more time and money if the siding and framing around the old window frame is damaged and requires rebuilding.

Pro Cost Diy Cost Pro time Diy Time Diy Savings Percent Saved

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To find more DIY project costs and to post comments and questions, visit www.diyornot.com and m.diyornot.com on smartphones.

Pro Cost — DIY Cost — Pro time — DIY Time — DIY Savings — Percent Saved

$612 — $285 — 6.9 — 11.0 — $327 — 53%

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