The Best Ways To Add Space To Your House

Choose an approach that adds space and value

New Home Construction; Framed Room With a View
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You already have the room on your property--somewhere. It's just a matter of carving out and creating conditioned living space from that room. Not only does more living space mean happier families, it means higher resale values for your house. But not all space-adding remodels are created equally. Some, in fact, are downright harmful to your home's value. Rated from best to worst:

Build an Addition Outward

If you can steel yourself for this long, expensive project, an on-grade addition will pay you back many times over—financially and emotionally. Building an addition is the only true way to "create space." Except for building upward, nearly every other way of creating space involves redistributing existing space.

Pros

  • You create an entirely new space, unhindered by existing structures. Usually, you do not need to vacate the house during construction. A true addition returns absolute maximum resale value.

Cons

  • Enormously expensive and never a do-it-yourself project

Build Upward

Commensurate with on-grade additions in terms of value, second-story additions are best when your available property is small.

Most homes will accept a second story, but it's not as easy as lopping off the roof and sticking another floor on top. Additional shoring up is needed.

Pros

  • This is a better way of gaining space than even building outward. The sky is the limit, as they say. Like building outward, this is one space-creating remodel that returns insanely high value upon sale.

Cons

  • Like building outward, this is very expensive and never a do-it-yourself project. It almost always involves vacating the house for some period of time.

Converting the Basement

Less popular than upward or outward additions, basement conversions still rank high because available floor space is often equal to existing first-story floor space.

Pros

  • Usually substantially build

  • Solid walls need little remediation for electrical wires

  • The floor rests on solid earth

  • Relatively low cost

  • Plenty of available contractors

Cons

  • Moisture is almost always a problem, but this can be mitigated.

Attic Conversion

Deceptively difficult, attic conversions are not the "shoo-in" they appear to be, as structural elements may need to be added.

Pros

  • Attics are pre-built for some degree of foot traffic, so you do not have to build in a lot of structural elements.

  • Because attics are near to the habitable floor below them, utilities (electrical, plumbing, waste, etc.) can be tapped into.

Cons

  • Attics are often oddly configured, with low-hanging ceilings and angled dormers. 

  • Though designed for storage and some foot traffic, attics are not meant for constant use. So, you will still need to strengthen the joists (by sistering or other methods) and lay down sub-floor.

Taking Down an Interior Wall

By turning two rooms into one room you create the illusion of space, rather than creating actual space. It's usually best to leave two rooms as two rooms. The exception is if those two rooms are especially tiny.

Pros

Cons

Repurposing a Room

Yes, it's the old Enclose-The-Porch-and-Turn-It-Into-a-Living-Room trick! If you're any kind of real estate follower, you'll recognize this type of conversion as one that causes Realtors to arch their eyebrows in doubt. If you decide to do this, be sure to closely align the function of the old room with the function of the new room.

Pros

  • Relatively easy and affordable

Cons

  • May compromise retail value

Converting the Garage

Usually, it's a bad idea to put money into this space-creation project, as you gain a low-value space by eliminating a higher value space. Not seen much anymore, the garage conversion seems largely a vestige of the Brady Bunch era. And for good reason: cars need homes, too. It is extremely tempting to convert the garage but resist the temptation. If anything, repeat to yourself, "This will drag down my resale value."

Pros

  • Relatively easy and affordable

Cons

  • May compromise retail value

Building a Separate Structure

If you're going to do this, attach the structure to your home and make it a traditional addition.

What We Don't Like

  • City permitting departments don't love homeowners who turn sheds into mother-in-law apartments.

  • The work of extending utilities 50 feet or more from the main structure to an accessory structure is usually more than most homeowners bargained for.

  • A properly built permitted separate structure can cost as much as an addition, yet give you less resale value.