Slab on grade / Discussions

How well do Legalett slab on grade floor forms work?

...on one, you just need to provide the building plans and Legalett engineers will provide you with complete stamped drawings and step by step install directions. It means your designer only has to concern themselves with what is above grade only, so let them know early so they don't spend your money on drawing up somethi...

Posted by Steve Sykes Aug. 18, 2019 Slab on Grade 3 responses

Is a vapor barrier necessary under a concrete slab with foam insulation and if so, where does go?

...on a Radon barrier radon evacuation stack is mandatory. To continue about radon – exposure to radon gas in homes is the second greatest cause of lung cancer. There is no way to test radon levels in a home before it is built and no way to install a barrier after a slab is poured, so I’d certainly install a radon barrier...

Posted by Grady 22 Aug. 17, 2019 Air and vapour barriers 3 responses

Where would I go for guidance on structural design of footings that sit on top of high-density insulation?

...on issue, but rather how the lateral (shear) loads get transferred from the concrete footing into the soil, via the insulation layer.  DJB It would be a structural engineer you're looking for, and while we have a team here that deal with everything LEED & Passive House related, structural questions about foundation...

Posted by Douglas Bennion July 31, 2019 Foundations and Basements 1 response

Can you elevate a slab on grade foundation?

...on ground level. As well because of snow accumulation.  My question is what would be the best way of constructing such a foundation? Or if it's even possible? I'd like the insulated slab on grade foundation idea but just wondering if elevating it 3ft. is possible? or is going with an ICF foundation, going down below fr...

Posted by Raoul Lions July 27, 2019 Slab on Grade 4 responses

Looking to build a small home as eco as possible, where do we start?

...slab on grade Choosing the best home insulation That’s a start to a few pages that will at least help you get your head in the game to get an idea of what you want. The budge you mention of 200K is not a particularly big one, and I hope that’s for the house alone and not the purchase of a lot, excavation, well, septic...

Posted by Jennifer Bisson July 12, 2019 Planning and Design 2 responses

What is the optimal setup for mechanical systems for slab on grade?

...ontractor and I must admit I'm feeling pretty guilty about the up to code builds I've done with essentially zero thought to energy efficiency! A lot of clients are on a tight budget and the idea of even spending 20% more on insulation was too abstract a notion, for something you don't actually see. Maybe the new role o...

Posted by Dave Nuttall July 6, 2019 Mechanical systems 1 response

Should I install two small electric hot water heaters - or one big one?

...one larger one.  Our house will be slab on grade, with the 4 bedrooms, 2 bathrooms, and laundry on one side of the house in 2 levels, and the kitchen and one full bath at the opposite end of the house on one level.  The water heaters will be electric, perhaps heat pump style.  Should I consider two hot water heaters, o...

Posted by Shaun B June 28, 2019 Hot water 2 responses

Can you help me choose between a slab on grade and pressure treated wood foundation?

...on wood buried in the ground is not something we have or ever would recommend.  And a slab on grade is an alternative to a basement, PWF or concrete, so I'm not sure where you're being advised to mix a PWF and a slab on grade, or how to even do that. A slab on grade floor consists of concrete and insulation (radiant he...

Posted by Margot Simonot May 20, 2019 Slab on Grade 1 response

Would you recommend Legalett over water radiant floor heat for a backyard studio in Toronto?

...on video as well as a few other resources on slabs. Legalett Solar Air Heated Slab on Grade installation video Slab on Grade Prefabricated Insulation Form Kit  Air heated floor Thickened-edge slab-on-grade technical guide

Posted by Christine Pountney May 2, 2019 Delivery: radiant, forced-air and decentralized 1 response

Are there any updates on the progress of the second demonstration house?

...on of the solar air panels that is new at this point. We expect to see about 60-70 % of the heat load but we won't know for sure until the winter of 2020 - 2021 when they are in full operation. I imagine you saw the installation video of the slab on grade kit here as well as the radiant tubing. 

Posted by dean c April 30, 2019 Solar thermal collectors 2 responses

Do I need to insulate under the footings of a frost protected shallow foundation?

...slab on grade premade foundation form kits, this is by a company called Legalett that provides slab on grade kits that mean you can stop scratching a hole in your head figuring insulation levels, they do it all for you. We just built one ourselves, here is a frost protected shallow foundation step-by-step construction ...

Posted by Jon Piana April 15, 2019 Slab on Grade 1 response

What are the factors I should consider for choosing between a slab on grade and basement?

...on question, and a hot topic that often brings dissagreement, but we like that though!  So much so that we have a page highlighting the pros and cons, check it out -  Slab on Grade or Foundation and Basement; Which is Best? But to address your questions specifically, I've included your questions in the response to make...

Posted by Shaun B April 2, 2019 Slab on Grade 3 responses

What should I look for if I want to buy a slab on grade house?

...on and contraction.  Check the exterior above grade portion, you may be able to notice any shifting issues there as well, you may have some indication as well of the insulation levels, and if it has been damaged in anyway.  Slabs also tend to be closer to the ground that a standard foundation, so I would inspect the bo...

Posted by terry northcott March 25, 2019 Slab on Grade 1 response

What are the options for radiant heat with a slab on grade?

...slab? Radiant heating is very comfortable, and there are really only minimal differences between the comfort that different systems will deliver. I would base my choice of systems mostly on cost and ease of installation, along with design considerations of the house. Warmboard sounds like a system worth considering if ...

Posted by August Wehrmann Feb. 3, 2019 Delivery: radiant, forced-air and decentralized 1 response

Can you help me decide between a foundation, slab on grade and crawlspace?

...ons that your parents or others may have had with a poorly constructed slab floor: Don’t embed water and power lines directly in the concrete, put them in a conduit so if there is ever any need you can pull the wire through and replace it. Don’t put ventilation ducting in the floor, tubes can be crushed when pouring co...

Posted by David Davenport Nov. 26, 2018 New foundations and slab-on-grade 1 response

How do you finish the exterior of slab on grade?

...slab on grade construction technique and wondering how  you finish the exterior of the footing insulation once the forms are removed, specifically the top of the roxul that would be exposed after building the exterior walls. Just to be clear when you say the 'top of the Roxul', the top horizontal edge of the slab insul...

Posted by Dave Derouin Oct. 18, 2018 Slab on Grade 1 response

How should I insulate under a concrete hydronic slab on stilts?

...on stilts. My second goal is to install concrete hydronic radiant floors. Does anyone have any experience with DIYing hydronic concrete slabs on stilts. How I would go about insulating underneath to avoid heat loss as the floor will be exposed to the elements being on stilts. Can the concrete floor be poured directly o...

Posted by Cam Smith Feb. 6, 2021 Foundation choices 1 response

Is hydronic slab heat appropriate in a super insulated home?

...onally not consider building a house on a polished slab on grade in a cold climate without heated floors. Heat moves from warm to cold, your body is 37C, and concrete is highly conductive. all those variables mean your floor will suck the heat right from your feet. The sensation is less pronounced with less conductive ...

Posted by Andrew Wright Feb. 3, 2021 Delivery: radiant, forced-air and decentralized 1 response