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Launch Slideshow

Figure 3. Instead of lowering the new mudroom floor to match the elevation of the old entry into the garage, as called for by the plans (left), the author took advantage of an extension to the garage roof (above) to create headroom above the old garage. This allowed him to raise the entryway and keep the mudroom floor at the same level.

Expanding a Kitchen

Foundation and layout

Expanding a Kitchen

Foundation and layout

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    As is often the case with remodels, building the addition would be easy; the tricky part would be the tie-in. The existing 15-foot-by-20-foot kitchen floor was out of level in three different directions. We excavated this foundation and laid out the footing, and we used the top of the floor joists at the center of the future opening between the addition and the existing house as our benchmark. After forming and pouring the 12-inch-deep by 24-inch-wide footing, we laid up the wall using 12-inch-wide concrete block. We terminated the top of the wall with a course of 8-inch block, creating a 4-inch-deep inner shelf that we topped with a 4x6 PT mudsill set on edge.
  • Figure 1. To establish an accurate benchmark elevation for the addition, a carpenter exposes the floor framing in the center of the proposed opening (left). The existing joists were later trimmed or shimmed  and in some cases reinforced with sistered 2x10s  to smooth out the transition into the addition and to prep the kitchen for new wood-strip flooring (below).

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    Figure 1. To establish an accurate benchmark elevation for the addition, a carpenter exposes the floor framing in the center of the proposed opening (left). The existing joists were later trimmed or shimmed and in some cases reinforced with sistered 2x10s to smooth out the transition into the addition and to prep the kitchen for new wood-strip flooring (below).

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    To establish an accurate benchmark elevation for the addition, a carpenter exposes the floor framing in the center of the proposed opening.
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    The existing joists were later trimmed or shimmed — and in some cases reinforced with sistered 2x10s — to smooth out the transition into the addition and to prep the kitchen for new wood-strip flooring.
  • Figure 2. The architect specified a pressure-treated pony wall for resolving a grade problem along the side of the house. The crew exposed the foundation and framing, applied a coat of cold asphalt to the rim-joist area (A), then installed PT sheathing (B). Next, after prepping the wall with 30-pound asphalt felt paper and metal lath, they parged the new and existing walls (C). A second coat of cold asphalt on the below-grade portions of the parged walls (D)  along with drainpipe set in coarse stone wrapped with filter fabric  helps manage water around the foundation (E).

    http://www.jlconline.com/Images/tmp2592%2Etmp_tcm96-1532016.jpg

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    Figure 2. The architect specified a pressure-treated pony wall for resolving a grade problem along the side of the house. The crew exposed the foundation and framing, applied a coat of cold asphalt to the rim-joist area (A), then installed PT sheathing (B). Next, after prepping the wall with 30-pound asphalt felt paper and metal lath, they parged the new and existing walls (C). A second coat of cold asphalt on the below-grade portions of the parged walls (D) along with drainpipe set in coarse stone wrapped with filter fabric helps manage water around the foundation (E).

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    The architect specified a pressure-treated pony wall for resolving a grade problem along the side of the house. The crew exposed the foundation and framing, applied a coat of cold asphalt to the rim-joist area.

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    After preparing the pony wall from the exterior, we installed PT sheathing.
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    Next, after prepping the wall with 30-pound asphalt felt paper and metal lath, we parged the new and existing walls.
  • Image

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    A second coat of cold asphalt was applied to the below-grade portions of the parged walls.
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    A drainpipe set in coarse stone wrapped with filter fabric — helps manage water around the foundation.

When I first reviewed the plans for the kitchen remodel shown here, the project seemed fairly straightforward. It featured a small addition on a new stem-wall foundation at the rear of the home, a typical suburban New Jersey expanded cape. The addition would allow the first-floor plan to be reconfigured, enlarging the kitchen and improving traffic flow, but the project also included considerable work on the existing house.

As is often the case with remodels, building the addition would be easy; the tricky part would be the tie-in. For one thing, the existing 15-foot-by-20-foot kitchen floor was out of level in three different directions, resulting in a 1-1/2-inch height difference with the adjacent family-room floor — a tripping hazard the family wanted to eliminate.

  • Illustration: The old kitchen was crammed between a bathroom and a staircase, and had poor flow into adjacent rooms and scant natural light (left). Bumping out the rear wall and moving the bath to the new mudroom allowed the kitchen to spread into the corner, where it shares space with the family room (below). Installing flush headers, as described in the photos on the opposite page, created a smooth ceiling between the rooms and opened up the adjoining eating area.
    Illustration: The old kitchen was crammed between a bathroom and a staircase, and had poor flow into adjacent rooms and scant natural light (left). Bumping out the rear wall and moving the bath to the new mudroom allowed the kitchen to spread into the corner, where it shares space with the family room (below). Installing flush headers, as described in the photos on the opposite page, created a smooth ceiling between the rooms and opened up the adjoining eating area.

Several new headers would also be required, including one for the 12-foot-wide tie-in opening between the addition and the old kitchen. To clean up the ceiling and help make the space feel larger, we also had to remove a large interior flitch-plate drop header and replace it with a flush header.

RRP Compliance

Since this was a pre-1978 house and our clients had three children ranging in age from three to eight, our first challenge was to manage risks from lead-contaminated dust and comply with the RRP rule. Fortunately, we were able to build the footing and foundation and frame the new floor system before even opening or entering the existing house, making dust control a lot easier.

Once we installed the addition’s subfloor, we isolated the existing kitchen with dust walls and called in our demo subcontractor to gut the room down to the framing. For the past several years, we’ve subbed out the demolition phase on projects like this, because it helps control costs and saves considerable wear-and-tear on our backs. We usually hire the same company (which is RRP-certified), and since it also does commercial demolition, it has the manpower and equipment — including trucks and roll-off containers — to quickly and economically take care of this phase of the project. The cost for its services on this job was about $3,000.

After the initial demolition and RRP cleanup and verification, we were able to proceed with the job using our normal dust precautions. In the end, our compliance costs were minimal, probably less than one percent of the total project cost.

Block Foundation

Though we sub out demolition, we typically block up our own foundations because it gives us more control over the schedule (see “Block Foundations for Small Additions,” 1/09). When we excavated this foundation and laid out the footing, we used the top of the floor joists at the center of the future opening between the addition and the existing house as our benchmark (see slideshow).

After forming and pouring the 12-inch-deep by 24-inch-wide footing, we laid up the wall using 12-inch-wide concrete block. We terminated the top of the wall with a course of 8-inch block, creating a 4-inch-deep inner shelf that we topped with a 4x6 PT mudsill set on edge. The new joists rest on this interior sill with their tops flush with the top of the outer 4x6 sill, an arrangement that allowed us to keep the floor framing close to the ground.