Floating deck with deck block and adjustable deck support- doable or do I need to dig

Question Icon
Posted by: from Scarborough
5/14/2021 at 10:26:17 PM

I would like to build a deck 2 feet off the ground, the area right now is covered by patio stones 18"x18". I need to remove those stones and dig about 6-8in, in order to keep the deck below 2 feet using deck blocks and adjustable deck support... is this ok to do or do I need to dig deeper to below the frostline- im in east Toronto...

User Icon
Ian in Edmonton
Date/Time5/15/2021 at 11:41:45 AM

As long as you're OK with a little seasonal frost movement there's nothing wrong with your idea and it's OK with respect to building code since the deck is less than 2' above grade.

When I worked for New Home Warranty I witnessed MANY failures involving decks supported by pilings frost-jacking (particularly homes with walkout basements) where the pile lifts and doesn't settle back over the next summer. it would have been better to use pad footings and allow for some seasonal fluctuation.

If those pads are supported on a thick gravel base it helps to reduce or eliminate frost movement depending on the thickness. Also pad footings supported on gravel soils are not required by Code to be below frost level.

User Icon
Date/Time5/23/2021 at 11:30:39 PM

As per Ian, good advice. Anything under 2 ft you do not need a permit but why not do it as well as possible? as you will get movement in Canada without pilings to code. Screw piles are not expensive $200 each, doing it this way will "guarantee" a pro job and "no" movement in future if at least 8ft pilings used. While there are exceptions in 20 years I have never had as call back doing it this way but many decks with just blocks invariably always move some or alot over the years.

User Icon
Date/Time6/16/2021 at 12:29:43 AM

Make sure to check your municipality in regards to the deck height. Just because you're 2' and under, it still needs comply with other requirements for it not to have a permit.

Other than that, what others have said, if you're okay with slight seasonal movement, you should be fine. The very first deck I ever built is on deck blocks on top of patio slabs and it doesn't even look like it's moved an inch.

Good luck with your project!

Search the TrustedPros directory and discover the best contractors in your area.

Find your home service pro
Great renovations start with a great contractor.

Since 2004, TrustedPros has been helping homeowners find the right contractor for their home improvements and repairs.

Post Your Project

Within hours you'll be comparing offers from top-rated professionals. It's free to post and you're under no obligation to hire.

Trustedpros Inc. does not warrant the accuracy, completeness, safety, legality or usefulness of any Content, or Whether Content is Current and up-to-date, and TrustedPros Inc. Shall have no liability whatsoever with respect to your use or reliance upon any content or for content being removed or otherwise ceasing to be available. Please refer to the terms and conditions of use of this websites for more details.

Get quotes from top-rated contractors