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Q: I’m thinking of finishing my basement. What do I need to know?

A: In terms of remodeling or finishing, basements have a lot going for them. The space is already built out structurally, and there is usually a set of stairs connecting the space to the main floor.

Still, basements bring their own share of challenges. Here are a few details to be aware of when considering finishing your basement.

If you are interested in using part of your finished basement as a bedroom, keep in mind that basement bedrooms need either a window or door to exit from in case of a fire or other emergency.

The window needs to be almost 6 square feet of net clear opening, with a sill no more than 44 inches off the finished floor. That usually means a casement window, which hinges open from the side.

If your basement is below grade, you may need to build a window well to accommodate it.

Another consideration is head height. If the finished basement ceiling will be less than 7 feet tall, you may want to consider either lifting your house or digging down the basement slab and footings.

These are both major projects and carry a substantial price tag, but a ceiling height of 8 feet or greater will help the rooms feel more spacious and less like a basement.

If lifting the house or digging down the basement slab is cost-prohibitive, there are a few tricks to make the low height less evident. You can talk to your contractor about moving ductwork to run along the walls in a soffit.

Another trick is to use can lights instead of surface-mount fixtures. Flush frame beams into the ceiling so that the joists hang off the beam instead of sitting on top of it.

Finally, installing larger windows with window wells will bring more light into basement rooms and create a feeling of openness and space.

You will also want to think about insulation. Basement walls are typically concrete or cinder block. To install insulation at the exterior walls, a wood-framed wall is built that creates space for insulation and separation between the concrete and Sheetrock.

You may also want to consider installing sound insulation between the concrete and Sheetrock and also sound insulation in the ceiling of your basement to reduce noise transmission between the basement and the main floor.

If you have decided to dig down your basement or replace the slab, rigid foam insulation can be installed under the concrete before it is poured. This will prevent heat loss to the concrete and the dirt below it.

Are you thinking of adding a bathroom to your new finished basement?

If so, you will want to check your sewer connections. In older homes the sewer line is usually a 6- to 8-inch cast-iron pipe. In newer homes you’ll be looking for a black or white plastic pipe

If the sewer line goes through the foundation wall above the concrete slab, chances are you will need a pump. If it goes down into the slab, the toilet and shower can usually drain by gravity.

A basement remodel is a large investment. The best way to ensure you have a truly functional space that meets code is to have an experienced designer or architect help with space planning and permitting.

When completed, a properly finished basement can give your home increased space that is both functional and attractive.

Anne Higuera of Ventana Construction LLC is a member of the Master Builders Association of King and Snohomish Counties’ Remodelers Council and provided the information contained in this article. If you would like more information or have questions about home improvement send them to