Home additions- Part 2 – The News

A concrete slab, with footings below the frost line, is another economical option but is only suitable when the addition is at grade level. The most common options for home addition foundations are the crawlspace or full basement. Both options allow for extra storage space plus a full basement leaves room for additional finished space in the future.

Pouring a foundation for a home addition is very similar to new construction. Your contractor will need to locate any underground utility lines before excavating. If you plan to save any landscaping features, such as a favourite shrub, you should make sure to communicate this to your contractor so proper arrangements can be made. If you are adding a full basement, be aware that your contractor will need to cut an entryway from the existing basement to the new basement. Concrete cutting can be a very loud and messy process, so be prepared.

The new foundation walls need to be carefully joined and sealed to existing foundation walls to prevent future problems. Pinning the two walls together typically involves drilling the existing wall and driving in rebar to act as a fastener between the two walls, sometimes with the use of a bonding agent. It will be necessary to remove any waterproof coatings on the existing wall before starting to ensure proper bonding between the two concrete walls.

The seam where the new foundation meets the existing one is called a construction joint, or cold joint, and will be subject to movement over time. It is crucial this area receives adequate attention and tight waterproofing. The new drainage system also needs to be tied into the existing one and working properly to prevent water entry into the basement.

Interior Demolition

Depending on the size and design of a home addition, some interior demolition work will likely have to take place. If walls are being knocked down, extra care should be taken where plumbing, electrical or HVAC lines are present. Ensure a contractor is wearing appropriate safety gear (e.g. eye injuries are common during demolition) and the main electrical panel has been shut off before starting.

Its always best to start demolition projects with a reciprocating saw rather than a sledgehammer, as a busted plumping pipe can cause some major damage fast. If removing a load-bearing wall, make sure a red seal carpenter who is equipped with the knowledge to ensure the job is completed safely is hired. A temporary support wall will be required while a beam strong enough to support the load is installed.

During any demolition project, drywall or plaster dust is bound to find its way throughout the house. Talk to the contractor about setting up a negative air machine before starting. Negative air machines work by suctioning air out of an area that has been boarded off typically with plastic sheeting to create negative pressure, ensuring dust, mold, or odours are contained. Contaminated air then travels through a scrubber and clean air is exhausted. This can make a big difference in a large demolition project, especially where homeowners will be present throughout the project.

Every Tuesday, Red Seal Carpenter Gib Thompson, owner of MacGibbons Contracting Ltd. in Stellarton, addresses a wide-range of home-related construction and maintenance topics. Readers can submit questions to macgibcontracting@hotmail.com or by calling at 902-695-5919.

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Home additions- Part 2 - The News