The High Performance Foundation

Build a home with a high performance foundation

In keeping with Passive House standards, a high-performance foundation in a humid climate like the Midwest must take into consideration four crucial control layers: water, air, thermal, and vapor. 

Thermal Control Layer

• R-20+ sub slab insulation to eliminate thermal transmission from the ground and maintain a comfortable temperature in the basement
• R-20 insulation on the inside of the foundation wall isolating the wall from touching any other layers of concrete

Bulk Water Control Layer

• Waterproofing on foundation walls and footings to stop moisture seeping in
• A capillary break that prevents moisture wicking up from the foundation footings
• A dimple board that allows water to drain and reduces pressure on foundation walls
• Interior and exterior drain tile to take water out and away from the home

Vapor Control Layer

• A vapor barrier that creates a tight seal, preventing excess air movement and moisture buildup
• Vapor layer is taped with Compego tape to seal it to the foundation wall and taped at all the seams and plumbing penetrations 

Air Control Layer

• 15 mm plastic sheet lines the insulation above compacted gravel and is taped to the interior side of the foundation wall to create a continuous air control layer

All of these details come together to create a foundation system that will stand the elements over time. Maintaining the same attention to detail through the mudsill ensures that the control layers are continuous up into the wall system.