Waterproofing Outdoor Igloo Style Oven

[Raffy]

Good Day WFO Enthusiasts,

I'd like to hear your waterproofing techniques for an Igloo style oven located outdoors. I live in a tropical country and when it rains it pours. Logic dictates put a roof or make a gabled house oven instead. But, I like the look and feel of an Igloo oven.

I'm electing to apply the following material on the concrete to waterproof it. Allgemeine-Bau-Chemie Philippines, Inc.

Your thoughts? What would be the best technique which requires little to no maintenance?

Raffy

[Neil2]

Re: Waterproofing Outdoor Igloo Style Oven

I looked at the link. What you want is something with a bit of flexibility. These things expand and contract during a firing cycle. I used an acrylic stucco and it seems to be holding up OK. I do however cover mine with a tarp during our winter rainy season.

[Tscarborough]

Re: Waterproofing Outdoor Igloo Style Oven

That product looks good, I would do 2 coats, one brushed horizontally, one brushed vertically, or if one coat, brush in a "W" shape overlapping strokes. I would also wait until I had fired the oven out to get all the cracking done before application rather than after.

[david s]

Re: Waterproofing Outdoor Igloo Style Oven

Be 100% sure that the oven is dry before applying a waterproof coating. This will probably take about 7-8 good cooking firings. If there is still moisture in the oven and you've waterproofed the outside, then moisture is locked in and can only escape from the inside. The heat tends to drive the moisture away from itself so losing moisture trapped in the outer parts of the oven will take ages.

[Raffy]

Re: Waterproofing Outdoor Igloo Style Oven

Hi Neil,

What do you mean by acrylic stucco? Is it a cement product with acrylic in it or do you mean acrylic sealant applied on stucco. I'm just a noob at waterproofing I'm not really familiar with all these products. Could you provide a link by any chance?

Thanks for the input!

Warm Regards,
Raffy

[Raffy]

Re: Waterproofing Outdoor Igloo Style Oven

That product looks good, I would do 2 coats, one brushed horizontally, one brushed vertically, or if one coat, brush in a "W" shape overlapping strokes. I would also wait until I had fired the oven out to get all the cracking done before application rather than after.

Hi Tscarborough,

Sounds like good advice. I'll definitely overlap the strokes like you said to ensure a proper seal. Thanks a lot!


Raffy

[Raffy]

Re: Waterproofing Outdoor Igloo Style Oven

Be 100% sure that the oven is dry before applying a waterproof coating. This will probably take about 7-8 good cooking firings. If there is still moisture in the oven and you've waterproofed the outside, then moisture is locked in and can only escape from the inside. The heat tends to drive the moisture away from itself so losing moisture trapped in the outer parts of the oven will take ages.

Hi David,

Thanks for the tip. I'll be sure to dry it out before applying the sealer. Fortunately its summer here now and I expect it will dry quickly. Is there a defintive way to determine if your oven is thoroughly dry?

Raffy

[Tscarborough]

Re: Waterproofing Outdoor Igloo Style Oven

The field test of moisture content is to tape a 12"x12" piece of poly to the surface and leave it though a heating-cooling cycle, i.e. a day and a night. If there is condensation on the poly there is too much moisture to seal/paint/stain the surface.

While this is not strictly applicable to typical oven wall makeups, it will give you a good idea of the moisture within the stucco itself. Provided you have fired out the oven, it should work as a valid predictor.

[Raffy]

Re: Waterproofing Outdoor Igloo Style Oven

Hi Tscarborough,

What do you mean by poly? Polystyrene? Sorry I'm still getting the hang of the construction terms.

Raffy

[Raffy]

Re: Waterproofing Outdoor Igloo Style Oven

I'll be sure to wait considerable time before waterproofing. But that "poly" technique really interests me. Once, I find out what poly means hehehehe.

Just to be safe, I'm thinking of firing the oven a day before waterproofing. Occasionally, I'll chuck in wood to keep the fire going every few hours, then, let it cool down the next day. Of course, I won't let the heat go to waste. I'll roast and bake some goodies for family and friends. Hell, why not make it a party hahaha!

[Tscarborough]

Re: Waterproofing Outdoor Igloo Style Oven

4 to 6 mil polyethylene sheeting, or what ever type of waterproof sheeting you have. Saran wrap, ziplock bags, a bread wrapper, whatever.

[Raffy]

Re: Waterproofing Outdoor Igloo Style Oven

Got it! Now I understand. So any moisture that has evaporated from the dome will condense on the sheet which will indicate that there is still water present. If there is little or no condensation then that would indicate that it is dry enough.

Thanks for that tip! Genius.

Raffy

[Neil2]

Re: Waterproofing Outdoor Igloo Style Oven

"What do you mean by acrylic stucco? "

It is not a cement product at all. It remains flexible. You can also get it in various colors. It is "water resistant" whereas traditional stuccos are not.


ACRYLIC FINISH VS. STUCCO FINISH

[trockyh]

Re: Waterproofing Outdoor Igloo Style Oven

Not to steal this thread, but along the same lines, I put a coat of the home brew mortar without the fireclay on my dome. How long does it need to cure before I put a brown coat/scratch coat of stucco? Or, is the homebrew about the same as the scratch coat?

Thanks,
Tom

[Tscarborough]

Re: Waterproofing Outdoor Igloo Style Oven

Actually, Neil, your standard acrylic finish is not flexible at all. There are elastomeric acrylic finishes, but even they will not bridge any cracks in the base over 1/8" and they are iffy on anything over 1/16". Unless you are using a system devised by a manufacturer and follow the details exactly, acrylic finish coat is not that good an option. As a rule, synthetic stucco is not a DIY material, and any issues you have will not be covered by the distributor or manufacturer. They normally require applicators to be certified.

Cementious is cheaper, more forgiving in terms of installation, and performs just as well.