UPDATE 2: Foundation Work
When the Yard is a Priority, You Change the Foundation
Considerations for designing and building a sound foundation are numerous, from moisture protection and planning for utilities to structural concerns and code compliances, but there are some more human-centered elements that make any addition worthwhile, starting with the foundation. When considering the addition, we decided to drop the entire mudroom structure one step from the rest of the home. In fact, our designers stepped the foundation and entire building assembly down 7″ from the main level, which meant that fewer exterior stairs would be needed to enter the home and take up space in the yard. While the need for more entry space along the back of the home made building an addition an important part of the remodel, our clients and their children used the yard frequently and wanted to retain most of it.
Prioritizing Things That Matter
Leaning into what’s important to the homeowner – this is the philosophy we bring to every project. Proposing an addition isn’t just about making a home bigger, it’s about gaining efficiency, proposing just the right amount of space to make a home better suited to the people who occupy it. Instead of having an overly deep mudroom with an equally deep foundation, we made the addition wider, resulting in even more yard-savings.
Digging into the Details – A Team Approach
Excavating the earth around the back of the home is an essential, initial step to getting the foundation ready. Local codes indicate how deep the foundation’s footings must be to get below the frost line to prevent buckling or other foundation failures. With a 42″ requirement for this area, the excavation team had quite some serious digging to do.
Our design team is the first to propose the foundation detailing, or what parts go into the foundation and how they connect with the rest of the home. With the decades worth of building experience on the team, the details are then reviewed by the entire office in an extensive red-lining process, where we discuss the strengths of the details and adjust as needed. We also review the drawings with the city and our own foundation crew, getting multiple trades and opinions on the best building solutions for our clients.
Composing a Foundation – Specifications Matter
Foundations may differ from project to project, but the role of any foundation is to distribute the weight of the assembly above with all its’ load bearing components to the earth below while protecting the home from excessive moisture. The specifications, or specs, are detailed instructions given to the construction team that outline the complexity and quality we require from the project. Here are some example details about this foundation:
- Footing Specs: 20 x8 concrete footings with 2-#5 continuous rebar
- Concrete Specs: minimum 5000 PSI concrete footings containing 2 parallel runs of 1/2″ rebar, 3″ from ground
- Rebar Specs: must be lapped at a minimum of 12″ and then bent around corners and stepped footings
- Frost Footings: maintain a minimum of 42″ below the finished grade
- Soil Specs: undisturbed natural soils or engineered fill to support footings
Crawlspace to Workspace
With the site excavated, we poured the footings and assembled the rebar within the specifications above and then began laying the concrete block to form the exterior of the foundation wall. Considering the required 42″ footing depth, our trades could more easily work within the new crawlspace to configure the home’s updated utilities. Beyond the foundation specs, part of finishing this stage of the process is using vapor retarders/moisture prevention products to protect the home from moisture and temperature fluctuations. On this project, a 2″ rigid insulation sits just outside the foundation wall, giving the home additional protection against the cold, Minnesota winters.
Inspections Protect Your Investment
The final step in the foundation build process is scheduling the inspection. The city inspector examined the foundation as well as the architectural drawings to make sure that the construction is correct, safe, and built to the specifications outlined in the plans. The inspector looked for things like proper insulation and moisture protection, foundation depth, and rebar placement, to name a few. With the inspection passed, the homeowner has even more confidence in the quality of the build and evidence of the longevity of their investment.