Waterproof outer door

[Greenman]

Re: Waterproof outer door

Thats a tough gig Dave. There are some valuable points made in your report and drainage is key. With that rain it would be a fair test for anything!

We got some solid rain in Bundy but not much wind. Dodged a bullet this time.

[NCMan]

Re: Waterproof outer door

Dave......sorry to hear about your flooding issues. I know you'll get it dried out, but what a hassle. It's also nice of you to share your story w/newbies just starting out or those who are in their planning stages. Perhaps you will save someone from having the same problems. As has been said many times on here, water is the enemy of our WFO's. Whether from above or below, we need to keep it out and address it during the build. And the use of vapor barriers is highly recommended, as you said. Best of luck to you and stay dry!

[cobblerdave]

Re: Waterproof outer door

Great
G'day
This year it was cyclone marcia. No I was not anywhere in the path of that , but the associated low and rains yes difinitely. I've pored out 370 mm out of the rain gauge in 4 days.
Outer oven door...... Worked well ..... Tick
Chimney cover .... A couple of bricks just in case the wind picked up .... Again a tick.
House bricks over dome and tile surrounds ...... Shed water like a champ...... Big tick
Grated drain in front of oven stand/ wood stowage.... Big X...
Dismal but the rain washed leaves and sticks filling the drain and grates. Same with the side of the oven filled with sticks and leaves and the water flowed down the front of the oven.u
The stand and the dry wood are now soaked. That moisture will wick up into the oven and its insulation and it will take time for it to dry properly. Rising damp is very real and capillary action really sucks!
Of course you'll build with a moisture barrier under the slab. But if I could build again I would include a secound moisture barrier under the insulation of my oven. Even if you think it could never happen to you a moister barrier is a very cheap and easily fitted thing. Next time you look at a pick of a completed oven have closer look at the pavement level at the front of the oven. 9 times out of 10 it's about the same. It's not something we all factor in when we start. So the pavement gets done last and is always a bit higher than you would like.
Regards dave
[ATTACH][/ATTACH]

[cobblerdave]

Re: Waterproof outer door

[QUOTE=david s;179634]

G'day
Anyone that has ever dropped a firebrick in a bucket of water will find out they soak up water real fast, they are not like a house brick which are designed to resist water.

Dave,
That is not always correct. I did an absorption test on my firebricks and was surprised to find that they absorbed exactly the same amount of water by brick volume, as my solid red bricks. The determining factor is the degree of vitrification the clay has been subjected to. Generally firebricks will have a lower degree of vitrification, because it's undesirable for a firebrick to contain materials that want to melt, but not always. A house brick is designed to be partly waterproof, but still have some breathability. Apart from outdoor oven builders there is little need to make firebricks waterproof. You can soak any given brick for 24 hrs and weigh it, then compare it's dry weight to calculate the water it can absorb.

G'day Dave....Thanks!
Why do you do this to me Dave?.... A soft red common will soak up as much water in 24 hrs as a firebrick ! You have had me thinking long and hard. Tempted to get out some brick and experiment myself. Not to disprove your findings but to caste new light on them. Perhaps put som upright bricks in a shallow dish of water and see how much wicks up, or tie some together with a clap strap and pour water on them in mass? I don't have the time to do this now but I might in the future when I finally burn enough wood in the stowage to find those fire bricks.
Perhaps too it might be a difference in the type of firebrick mine are only "light Duty" firebrick.
Your right about the degree of vitrification being a factor. The house brick and commons that form my dome cover do a great job of protecting the insides from the wheather. They are not sealed at all and do the job quite well enough without the need for any extra sealing.
Those firebrick on the hearth are a different matter. They take up the water at a great rate. I know what happens when you pour a cup of water on them. Its doesn't have a chance to run off it just goes straight in. Yes the cracks between the bricks are a factor I'm sure but the fact remains they soak up water fast. The speed at which it happens is the difference between them and a brick common I'm sure. Sure I could slow this down by pre-wetting the firebrick, but in the case of an insulated hearth your screwed any way, the waters well on its way into the insulation.
A summer storm and its associated wind and driving rain last for an hour to an hour and a half....max. If the door works for a least this time I'm a happy man.
Thanks again

[cobblerdave]

Re: Waterproof outer door

Hi Dave,
Have you considered a couple of spring loaded door stops fitted on the inside of the door to press against the top or bottom of the door opening[/QUOTE]

G'day
When I first saw this I thought "crap this is the least possible thing for me to fashion" I really not a metal worker. But it stuck in my mind and I thought long and hard. The top of the door is the most likely to be blown open being the furthest from the bottom, the pivot point. Some sort of internal spring would be great. I got a piece of aluminium folded it in 1/2 and put it at the top and shut the door. Makes a great difference, definitely hold the top better the bottom rock solid already with the weight.



My plan is to include this clip at the top
Thanks Dave

[cobblerdave]

Re: Waterproof outer door

One problem about having any door on your oven, from a weather point of view, is that it holds any moisture in as well. A couple of wet seasons ago my oven got wet and actually started growing mould on the inside of the door. It may be better to remove the door altogether to allow the inside of the oven to breathe. Just try to remember to replace the door before it rains again.

G'day Dave
Yes your right there's no need to seal things in like a Tupperware lid. The seal wasn't required on Mk 1 so I will not add to the final version

Regards dave

[cobblerdave]

Re: Waterproof outer door

Another option would be marine ply and a marine varnish finish if you want to keep it organic.

G'day Steve
That's a great is idea, didn't consider it till you mentioned it. I could also run a router over it making boards widths like the stowage doors so it ties the overall look together. I goggled bunnings and its not expensive either.

Regards Dave

[david s]

Re: Waterproof outer door

[QUOTE=cobblerdave;179507]G'day
Anyone that has ever dropped a firebrick in a bucket of water will find out they soak up water real fast, they are not like a house brick which are designed to resist water.

Dave,
That is not always correct. I did an absorption test on my firebricks and was surprised to find that they absorbed exactly the same amount of water by brick volume, as my solid red bricks. The determining factor is the degree of vitrification the clay has been subjected to. Generally firebricks will have a lower degree of vitrification, because it's undesirable for a firebrick to contain materials that want to melt, but not always. A house brick is designed to be partly waterproof, but still have some breathability. Apart from outdoor oven builders there is little need to make firebricks waterproof. You can soak any given brick for 24 hrs and weigh it, then compare it's dry weight to calculate the water it can absorb.

[Toomulla]

Re: Waterproof outer door

[QUOTE=cobblerdave;179507]G'day
Anyone that has ever dropped a firebrick in a bucket of water will find out they soak up water real fast, they are not like a house brick which are designed to resist water.
I found I needed a waterproof door to prevent wind driven rain from soaking the hearth firebrick. Any water on them and the moisture wicked straight into the insulation layer, and was always a lengthy task to dry out.
I wanted it attached well so it didn't become a wind driven missile during our summer storms. A neighbour was nearly taken out by my BBQ lid in a storm one year, so this was important.
I didn't want to have any hinge's or fasteners drilled into the front of the oven so I came up with this


Hi Dave,
Have you considered a couple of spring loaded door stops fitted on the inside of the door to press against the top or bottom of the door opening

[david s]

Re: Waterproof outer door

One problem about having any door on your oven, from a weather point of view, is that it holds any moisture in as well. A couple of wet seasons ago my oven got wet and actually started growing mould on the inside of the door. It may be better to remove the door altogether to allow the inside of the oven to breathe. Just try to remember to replace the door before it rains again.

[Greenman]

Re: Waterproof outer door

Hey Dave - I see nothing much to be improved on with your door. You already have MK II in planning by the sounds and with something like aluminium checkerplate that will cop the weather as an exterior finish and a rubber seal I reckon you are on the money. Another option would be marine ply and a marine varnish finish if you want to keep it organic.

You are right about the brick being likely to find your foot - I had the whole door blow off the bench onto mine a week ago. Bloody Murphy and his law!

[NCMan]

Re: Waterproof outer door

Dave.....I think you did a great job w/it and that was all I could think of. Perhaps someone else can think of something to help. Lots of creative folks on here.

[cobblerdave]

Re: Waterproof outer door

G'day
No apologies required.
Yes I am looking for any new ideas. I just thought I'd covered those. Nothing new either it's just a slightly different take on the folded steel door you see available with some forno ovens.
Regards dave

[NCMan]

Re: Waterproof outer door

Sorry if you thought I was picking it apart. I think you did a great job w/your door. You asked for ideas and my intentions were to offer help. My apologies.

[cobblerdave]

Re: Waterproof outer door

G'day
That's what the. 2 in aluminum collar does . It fits inside the oven entrance . Sorry I should have made the scan a little clearer.
I even cut a "drip cutter"with a file closer to the door surface to stop the drips from heading back . Seems to work . Thanks for the input
Regards Dave
Ps NCman feel free to pick the sh!t out of anything else . I'm stuck with a workable waterproof door. Temporary materials but it could be better before I build the permanent door.