Finishing a basement is an exciting time for many homeowners: the liveable area of the home is being increased; an older child will have a private space of their own; a guest bedroom will be available to friends and family; the kids will have a dedicated play area; or there is finally a nice space for that home office or workshop.

When you decide to finish the basement you will encounter a number of challenges, such as:

• Selecting/designing the best layout to meet your needs;
• Establishing the budget for the project;
• Deciding on whether to do the work yourself or hire a contractor;
• Selecting the contractor; and
• A myriad of related details.

AquaGuard Injection & Waterproofing® does not provide basement renovation and construction services; however, we have encountered so many waterproofing related issues over the years that we believe we should share our experience with you so that you will be able to avoid water infiltration problems in the future and the associated damage it causes.

If you follow the link below you will observe that water can enter your basement in many different ways.

Sources and evidence of basement leaks

It is of vital importance that you carry out a detailed visual inspection of your basement for signs of water ingress before you start finishing your basement. If you notice any cracks or other irregularities such as mineral or soil stains, efflorescence, poorly mixed concrete (honeycombing), damp spots or dark stains on the concrete, you should consider having waterproofing done before you close the walls. If leaks occur behind your finished basement walls you will likely end up with mouldy drywall, baseboards and framing, damaged flooring, mouldy insulation, and ruined furniture. Aside from the detrimental health implications associated with mould, if there is ever a leak, the wall will have to be cut open, the drywall replaced and repainted, the flooring may have to be replaced, and some of your damaged furniture may have to be thrown out.

Call AquaGuard Injection & Waterproofing™ at 1.888.284.2384 to arrange a complimentary inspection. We've been in thousands of basements so we know where to look and what to look for. You should expect that signs of water infiltration problems or cracks will likely be found. It is advisable that you budget for this in your renovation and construction plans.

You may not wish to spend your hard earned money on preventive basement waterproofing but, in the long run, it is probably in your financial interest to do so.

Do I have to fix cracks in my poured concrete foundation which have never leaked?

Note: When you have any waterproofing done you must test the repair(s) aggressively before you close the walls. Waterproofing, prior to construction, is so vitally important that the Canada Mortgage and Housing Corporation (CMHC) has published information specifically on this subject; for more information click on the links below:

Renovating your basement – structural issues and soil conditions
Renovating your basement – moisture problems
Avoiding basement flooding

Recommended Practices In Basement Finishing

Hiring the “right" contractor is a complicated process which is beyond the scope of this discussion; however, there are a few practices that your contractor, or you, should follow to minimize damage resulting from water infiltration:

1. Installed drywall must never come into contact with the concrete floor; it should be installed 1cm above the floor; this gap won't show as the baseboard will be covering it. If drywall is allowed to absorb water from the floor, mould will grow behind your drywall.

2. There must be a capillary break (vapour barrier) between the sole plate of the wall framing and the concrete floor; otherwise, the sole plate will rot from the moisture emanating from the concrete floor and/or from water on the floor coming from a basement leak.

3. If you plan on installing a fireplace in the basement, try to avoid having the chimney exhaust below grade. This type of exhaust necessitates a special housing on the exterior to vent above grade, however, if a below grade hole in the foundation is required it will constitute a major waterproofing vulnerability.

4. You should allocate some budget for waterproofing work. We recommend a minimum of $1000 for a poured concrete foundation and $2500 for a concrete block foundation. If you elect to forego the waterproofing and/or don't budget for it, you may be forced to either increase your budget or sacrifice some of the features you initially chose.

Note: Your contractor will be hindered by waterproofing work if it is done during construction. Sometimes contractors won't even mention anything about leaks or potential leaks because they don't want their work delayed or they don't want to approach you with additional costs.

Note: There are excellent renovation contractors in the industry and each trade has its experts; given our experience with basements and waterproofing issues, it is in your interest to deal with specialists in this domain. Call us today at 1.888.284.2384; we're here to help you!

Basement design and feature considerations:

1. Floor drain location – Floor drains are incorporated into basement floors in order to get rid of water. Make sure that water entering your basement will be able to flow towards and into the drain. Take this into consideration when planning the height of your flooring and the locations of dividing walls and, if necessary, install additional drains.

2. Sub-floor installation – The installation of a sub-floor can be useful as it allows water to travel beneath the floor without damaging the finished flooring. However, sub-floors significantly impede a waterproofing contractor's ability to locate the source of a leak. Additionally, if there is significant water infiltration and, consequently, hydrostatic pressure, it is possible that water will come up through the subfloor between the sheets of plywood or subfloor tiles.

3. The use of spray foam insulation – It is advisable that you inject all poured concrete foundation cracks, that will be covered over, with spray foam insulation because the insulation will effectively cause water to be trapped in the cracks. This trapped water will permeate the concrete and weaken it. Also, if subjected to sub-zero temperatures, the trapped water will freeze and expand; this expansion can easily cause a crack to widen. With respect to concrete block foundations, the pooling of water in the blocks will saturate the blocks and affect the strength of the foundation walls. Caution: we recommend that you avoid using spray foam insulation as a means of waterproofing a concrete block wall.

4. The choice of ceiling finishing – Here you have three typical options:

a. A stucco finish over drywall;
b. A smooth drywall ceiling; and
c. A drop ceiling.

Given the potential for plumbing leaks we would recommend smooth ceilings and drop ceilings because they are more easily repaired when affected by water damage.

5. Flooring Selection – The best way to ensure that you don't have to replace basement flooring in the event of a basement leak or a flood, is to install a ceramic tile floor. Wet carpeting is difficult to dry out without commercial equipment, laminate flooring swells and incurs significant damage when exposed to water, and hardwood flooring will swell and buckle.

We recommend that you consult the Waterproofing & Health Related Links page, in particular the Oak Ridge National Laboratory - Builder's Foundation Handbook, as it contains alot of relevant information concerning basement finishing and/or renovation.