Room Additions

One room, built off the side or back

Plenty of households do not need a new wing. They need one more room: a bedroom for a second child, a playroom, a place for the piano, a den with a door that closes. A room addition gives you that without the scale of a large project. The footprint is modest and the foundation simple, so most of the design thinking goes into where the room sits and how you walk into it.

Placement drives everything else. Off the back, a room usually has more room to work within the setbacks and less effect on how the house looks from the street. Off the side, it may run into a side-yard setback on a narrow lot, or crowd a driveway, a well or the septic field. We walk the property with you and look at the yard, the existing windows and the path into the room from inside before anything is drawn.

That inside path matters more than people expect. If the only way into the new room is through a bedroom or a bathroom, the house ends up working worse than it did before. We look for a hallway, a living room wall or a dining room that can give up a doorway without losing what makes that room useful.

The room also has to suit the house from the street. A one-story room on the back of a two-story colonial can look right with the correct roof and trim. The same room stuck on the front of a Cape rarely does, which is one more reason most room additions go off the back.

Choosing the foundation under a small footprint

A single room can sit on a full foundation, a crawlspace or a frost wall with a slab. Whatever the choice, footings in Massachusetts go below frost depth, commonly about four feet, so the room does not move separately from the house when the ground freezes and thaws. A room set on shallow posts or a floating slab tends to crack away from the main house over time, and that crack lets in water and cold air.

A crawlspace is a common answer for one room because it keeps the new floor at the same height as the old one and leaves access for plumbing or ductwork. It has to be insulated and sealed to the current energy code, and many Massachusetts towns have adopted the stretch code, which raises those requirements. A slab can make sense where the house itself sits low, or where the room is meant to be a step down.

We also find out what is under the yard. Ledge, a high water table, an abandoned oil tank or a buried utility line can change the plan. Where there is any question we dig a test hole or call for a utility mark-out early, so the foundation is chosen on facts rather than hope.

If the inspector asks for something, you hear about it that day, along with what we are doing about it.

The roof tie-in is the hard part of a small addition

On a one-room addition, the roof connection is where most of the skill goes. A shed roof can run off the existing wall below the eaves, which is simple but limits ceiling height and needs enough pitch to shed snow. A gable roof with its own ridge looks more like part of the house but has to meet the main roof in valleys that are flashed properly. Which one fits depends on the existing pitch, the eave height and the windows above.

Ice dams form where heat escapes into a roof and melts snow that then refreezes at the cold eave. A small roof added to an old house is a common place for them, because the joint between the two is hard to insulate and vent well. We plan the insulation, the ventilation path and the ice and water membrane at that joint as a single detail, worked out together so nothing falls between trades.

Then we match what you see from the yard: shingle color and exposure, fascia and rake trim, the gutter line. A room that looks bolted on makes the whole house look worse, even when the room inside is good.

Opening the existing wall into the new room

Once the new room is framed and closed in, we cut the opening through the old exterior wall. Before that day, we have already checked whether the wall carries load from the floor or roof above. If it does, we install a header sized for the span and support the structure while the wall is open. If the wall carries wiring or plumbing, licensed electricians and plumbers reroute it, as Massachusetts requires.

The day the wall opens is the dustiest day of the job, so we plan for it. Dust walls go up inside, floors are covered along the path, and furniture near the opening is moved or wrapped. In a house built before 1978, we treat the paint on that wall as possibly containing lead and follow lead-safe work practices until we know otherwise.

Inside, the trim, the floor transition and the ceiling line all need to meet cleanly. Old plaster walls do not take a new drywall patch without a careful seam, and old floors are rarely level. We plan those transitions ahead of time so the doorway into the new room looks like it was always there.

If the new room will be a bedroom, its windows are sized for emergency egress under the building code, and on a septic property the extra bedroom brings a Title 5 review that we check before design.

Your updates while the room goes up

A room addition is small enough that some contractors treat it as something to fit in between bigger jobs. We do the opposite. You get a written scope before we start, a schedule that we update as inspections pass, and a short message whenever something changes. If the inspector asks for something, you hear about it that day, along with what we are doing about it.

The inspections follow the usual sequence for new construction under the state building code: footings before the pour, rough framing, rough electrical and any plumbing, insulation, and final. We schedule each one and do not close a wall until it has passed.

Steve, who has 20 years in the trade and has run Modern Remodeling for the last six, is the person you deal with. The site is cleaned and closed at the end of every day. When the room is done, we walk it with you, and it is not finished until it looks and feels like part of the house.

See the rest of our additions work, or browse the gallery for rooms we have finished.