Room Additions in San Marino With a Closed Seam
San Marino room additions with the new footing sized against the old one and the joint framed and finished so the seam between them stays closed.
"Will the new room crack away from the old one?" An owner can raise that on our first walk around a San Marino house, and the honest answer starts underground. A new footing poured beside an old one has to bear on soil the engineer has judged, at a pressure close to what the old concrete already puts down. Otherwise the two can settle unevenly and pull the seam open.
Reading the old footing
A short length of the existing foundation is uncovered by hand where the addition will join. We record its width, its depth into the ground and whether steel shows at any cracked edge. The engineer uses those figures to size the new footing so the two bear on the soil in a similar way. Where the engineer cannot judge the ground from what is exposed, a soils report may be asked for, and the building department reads it alongside the drawings. Dowels epoxied into holes drilled in the old concrete then lock the two pours together at the joint.
Framing the seam to stay closed
Above the footing, the joint is framed to move as one piece. Floor sheathing runs across the line with solid blocking under the edge. Metal straps tie the top plates of the old and new walls together, and shear walls on each side connect down through the floor to their anchor bolts. Outside, a control joint in the stucco at the inside corner gives any small movement a planned place to show. Inside, the drywall seam lands on solid framing. We look at the joint again at the framing inspection, while it is still bare, against the detail sheet.
About our room additions serviceEverything we do in San Marino
Room Additions in San Marino: questions
The engineer finds out by comparing the weight of a second level with what the footing and soil can take. That means knowing the footing's size and whether it holds steel, which a test hole and sometimes a soils report show. If the concrete is too small, the plans add width or new pads, and that work is inspected before upper framing.
Through the floor, the walls and the roof, each joined separately. A ledger bolted to the old rim, or hangers on it, carries the new joists. Straps lap across the top plates at the break. Roof sheathing continues over the joint where the layout allows, and flashing is woven into each course of roofing. The cut into the old wall stays as narrow as the connection allows.
With the permit open and the crawlspace already exposed beside the new footing, it is a sensible time. Bolting the old sill to the foundation and bracing the cripple walls beneath the original rooms can join the addition's drawings. The engineer reviews the old foundation first, and the scope carries only the items that review supports.
Room Additions in other cities
More we build in San Marino
Book an inspection in San Marino
Describe the house and what it needs. We look at the structure first and send the quote in writing.