What to Do When You Have Mold in Your Crawlspace

moisture and mold in crawl space of Toronto homeDo you have a crawlspace in your home?  Often times, the crawl space is the dark, damp space in your home where funky things grow and live….and the place you stay out of unless absolutely necessary.

“Crawlspace” is an area in your home where you have to crawl around on your hands and knees. This can include tight areas in attics as well as under floors. The lack of access is why we often don’t see what’s going on there, but it can effect the rest of the home if left unchecked.

Why It’s a Problem

If you want to avoid larger repair costs later on, and potentially a reduced price (or lost deal) if you sell your home, you have to worry about the things you don’t see. For example:

  • Mold only grows where there’s humidity caused by moisture. Where’s the moisture coming from?

  • The mold may cause the floor timbers to rot, and eventually collapse – although this usually takes many years.

  • Property inspectors know about these problems. Mold in crawlspace is something they look actively for.

This all adds up to a very real threat to the value of your biggest asset – and that could mean the price of your home coming down quite sharply if a home inspection reveals water and mold infestation problems up there.

mold in crawl space

Gaining Access

As a general rule of thumb, builders should provide access to space beneath a floor. However, with builders, this isn’t always the case. It’s often simplest is to install a simple trapdoor. If your home is carpeted (or you love wood too much to do that) then your only remaining option is to create access from the outside.

Remedial Action

You must find out where the moisture coming from first and fix it. In theory, it’s unlikely to be rain water, because of damp courses required by building regulations. However, it’s not uncommon to find rockeries and flower beds set against walls that are meant to be above ground. If that’s the case, get rid of them immediately, and make sure the garden slopes away gradually, everywhere.

A second cause may be ground moisture welling up. This is especially possible if your house was built on trench foundations as opposed to on a concrete slab. The best solution is to lay down a vapor barrier. This is a series of polyethylene plastic strips with at least a one-foot overlap and taped joints. It’s a good idea to pin them down with a few bricks here and there.

Architects and builders know that crawlspace close to the ground inevitably becomes humid because of warmth transmitted from above. Every wooden floor should be ventilated with airbricks, which should be positioned to benefit from prevailing winds. Many houses are built off spec plans that take no account of spatial positioning. Sometimes, a few well-placed additional airbricks may solve a crawlspace mold problem on their own.

Practical Considerations

Many times accessing the crawlspace in your home can be difficult, even by professionals.  If you suspect water and mold problems and are unable to determine where or the extent of your moisture problems, you’ll probably want to call someone in to find the source of your moisture and mold problems.

Nusite Group has been serving Toronto and the GTA for over 30 years.  We specialize in foundation waterproofing, moisture and mold removal, and foundation repairs.  Contact us today to schedule a free estimate.

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NuSite Group is a Toronto based basement waterproofing and foundation repair company that specializes in Basement Waterproofing, Basement Lowering, and Foundation Repairs. Call us today at 416-622-7000 or 905-731-1228 for a free in-home estimate and inspection.

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