High or Low?

[Virgil]

Is there any particular problem with building the oven at deck level, say 4 feet above the ground as opposed to haveing it directly on the ground?

[RTflorida]

Re: High or Low?

Not sure exactly what you mean. Are you asking if you can build your oven to a workable height for a raised deck? Yes, it can be done. You don't want to attempt building on the deck, it must have a suitable foundation under the oven. Wood is not a suitable foundation system for an oven - it expands and contracts, which could cause serious cracking issues to a brick/masonry oven. Also, a finished oven (dome & hearth) will weigh somewhere around 2500+ lbs, so a stable foundation is critical.
In your case, I would recommend footers, then the support slab and the concrete block foundation. I am not a mason or structural engineer, so exactly what additional reinforcement would be needed to get to the height needed, I don't know.
Another option would be reinforced concrete piers (sono-tubes) to support the hearth and dome.
I believe someone on the forum actually used very heavy steel posts embedded in concrete for this same situation.
You have several options, just make sure your foundation runs deep enough to support the top heavyness you are creating.....not to mention any frost heave created in the winter (although I don't think this is that great a problem in your area).

RT

[Archena]

Re: High or Low?

What RT said.

A lot of cob (clay) ovens are built on the ground or on low foundations but that seems to be either a desire to make a traditional oven (depending on whose tradition, naturally) or to avoid having to build a stand. Those designs are for people with better knees than mine.

I'm going to build a stand - actually, you can even buy them - but my plan is to use a card table and something to raise it to decide on my final working height. Remember to allow for the height of the hearth itself when you are making your calculations. Most hearths seem to come in around four inches so a four foot stand would have a four foot four inch working height.

[Virgil]

Re: High or Low?

Thank you. I figured that I could not build it directly on the deck ... but rather just off it. And I also figured it would be alot more costly .... but She Must be Obeyed....

[Archena]

Re: High or Low?

Thank you. I figured that I could not build it directly on the deck ... but rather just off it. And I also figured it would be alot more costly .... but She Must be Obeyed....

<slaps forehead> Oh, I see what you mean now. It depends on the strength of your deck. It's possible with reinforcement - just like putting in a hot tub. putting the stand directly on the ground alongside the deck is easier and probably less costly than reinforcing the deck. Also, you have to be very careful if the deck is attached to the footer - the extra weight creates more stress on the bolts and you'll likely need to reinforce that as well.

If you do decide to build on the deck consider buying the stand from FB. The metal stand is much lighter than a masonry one.

[n2iko]

Re: High or Low?

How high is it from ground to the top of the deck? You can just extend the block base up to where you need it. You only have to please the aesthetics
and SWMBO.

[Virgil]

Re: High or Low?

Easier said than done on the latter point but only 4-6 feet on the deck height depending on where I build it. Thanks.

[david s]

Re: High or Low?

If your oven is small enough you can easily put it on a steel stand and screw it into the deck, but make sure the stand spans a couple of bearers. Also a good idea to put some alum checkerplate or something similar under the oven mouth to catch any hot dropped coals. You wouldn't want your deck to burn.

[RTflorida]

Re: High or Low?

Food for thought - The average add on patio deck is NOT reinforced enough to withstand the weight (unless you are using the most light weight materials) of an oven. Most decks have 4x4 posts imbedded 8 ft. apart with either 2x6 or 2x8 joists under the decking.....trust me, I've seen several people install hot tubs over this and a year later need help draining and moving the hot tub and rebuilding the deck to eliminate the sagging. If you choose to mount it on the deck, add extra posts and joists BEFORE you start on the oven.
I would never recommend that someone just build it on top of the deck.......without knowing how the deck is constructed. Sounds simple and you may know someone who has done exactly that with no ill effects....but for every one of those "successes" there are 2 people who have had to reinforce/rebuild their deck after the fact.
I'm not a contractor, but I sell to the trade and visit jobsites all the time (not to mention I have built many decks in my younger "laborer" days).

RT

[Virgil]

Re: High or Low?

Right you are RT. I think the way to go is to build it up from the groud and just have the deck built along side it. The good news is I am doing the deck and the oven at more or less the same time so it should not be too difficult. I
figure it will get more use if I have the oven more conveniently placed to our indoor and outdoor eating areas....

[david s]

Re: High or Low?

I agree about the excessive weight factor, which also goes for brick fences and letterboxes with inadequate foundations, however if your oven only weighed around 200 Kg (400 lbs) like a Primeva oven, that would be the equivalent of two big blokes standing side by side on the deck and the structure should be plenty to hold that weight.

[RTflorida]

Re: High or Low?

Virgil, your idea sounds pretty cool. I've seen a couple of decks built up to and around masonry firepits....they really looked good.

RT

[Archena]

Re: High or Low?

I agree about the excessive weight factor, which also goes for brick fences and letterboxes with inadequate foundations, however if your oven only weighed around 200 Kg (400 lbs) like a Primeva oven, that would be the equivalent of two big blokes standing side by side on the deck and the structure should be plenty to hold that weight.

True, but it's the four big guys (800 lbs) milling around the oven (400 lbs)playing with the fire that will overload the deck.

Sounds like Virgil has his plan, though.

[tigersmith]

Re: High or Low?

Hey Virgil,
Sounds like you are planning to do what I am. I have an existing deck that I plan to remove the railing on. I would then build up to the deck level and build on top. I will try to attach a few Sketchup pics, that I think will show my plan.

George Stein

[tigersmith]

Re: High or Low?

Let me try this again.