crawlspace-ventilation / Green Building & Sustainable Home Renovation Information & Advice

Crawlspace insulation - be careful to get it right A crawlspace comes with all the downsides of a basement, but it is just too low a space to be functional either beyond the folded plastic christmas tree and a couple of boxes of baubles. Unless there is a good reason for it, going through the process of pouring a footi...

Radon Gas in Crawlspaces & Basements - why is it a problem? Radon gas was not high on the radar of builders and home owners over the last few decades, but as it is the second leading cause of lung cancer (after smoking) in the USA & Canada, it is quickly becoming a household term. Many newer homes will have rad...

What is the difference between a slab on grade and a crawl space? A slab on grade, or ‘frost protected shallow foundation’ is exactly that, a slab of concrete on the ground. There’s more to it of course, but let’s start with a ‘win’ in the comprehension department shall we?  A slab on grade rests directly on the groun...

What is the difference between a slab on grade & a crawl space? A slab on grade, or ‘frost protected shallow foundation’ is exactly that, a slab of concrete on the ground. There’s more to it of course, but let’s start with a ‘win’ in the comprehension department shall we?  A slab on grade rests directly on the gro...

All homes need ventilation, whether natural or mechanical with an ERV or HRV system. Buildings and houses are no longer constructed leaking heat and moist air the way they used to be; we now build them as airtight as we can, especially Passive House or LEED certified homes. This makes mechanical ventilation essential i...

Is an insulated slab on grade the best foundation choice? Or is a basement better? Traditionally, home construction often starts with a concrete basement foundation - But is that the best choice?  The first factors to consider when designing the foundation system for a home are lot size and soil conditions. When space ...

In order to ensure comfort and get the most from the various systems of our house air needs to move around. Our air source heat pump and our heat pump water heater work together in boosting the efficiency, and the ceiling fan is a big part of making that happen. This video explains the relationship between those syste...

Homes built in the last 40 years in Canada are relatively airtight. Before that we generally relied on leaky uninsulated walls to provide fresh air and prevent mold and mildew, and they did that very well. Cost and comfort had us adding insulation, but not necessarily sealing our walls. The folly of this was quickly re...

Why cleaning HRV units is so important  When any machine has its normal operation hampered, it will reduce its efficiency and ability to function properly. Many of us are probably guilty of forgetting about basic maintenance of some of the mechanical equipment in our homes; keeping your HRV (heat recovery ventilator) c...

Radon gas maps - levels by State or Province Radon maps show where the risk of radon contamination in homes is the highest, But finding the local risk level on a radon map is not a clear indication of safe or dangerous levels of radon gas in a home. For example, below are official maps of the high-risk radon gas areas ...

Slab on Grade foundation, detail design; the basics There are many different soil conditions and corresponding slab designs. This page is about how to build a thickened edge concrete slab on grade FPSF footing on soil with a high water table to prevent frost heave, by first installing drainage below the slab.  Related ...