The most important aspect of the dome is to make it watertight and durable so that it won’t fall apart after two or three years
If it is not watertight the Styrofoam will eventually soak up water, if it is not protected.
So I looked around for different solutions.
First I put on 4 layers of newspaper and diluted wooden glue. 4 layers went on to give it a smooth surface.
After this was dry I put on a grassfire net and lamination epoxy NM 456.
This product is exceptionally well suited for the job and went on without problems. This epoxy is produced here in Sweden by a company called Nils Malmgren AB and is the best material I used for this project, for information se my links page.
Within 24 hours I put on 2 extra layers making it a total thickness over 4 mm this in combination with the glassfibre made the dome into a totally watertight boat hull.
But then there was the problem with the weight, it was to light and a gust of wind would easily throw it into my nabours garden.
So I went along with Joe’s idea of putting a layer of stucco on top of it but with one or two minor modifications.
First I used ultra fine quarts sand and a component called fugolastic to make it both smooth and elastic to avoid cracks, onto these 2 layers of siliqua paint was applied, that’s it! I thought.
The same winter it seemed that the stucco was put to the test with the result of small cracks (on the perimeter seal ring only).
So I decided to play it safe and applied 2 layers of epoxy on top of it followed by 2 layers of 2 component boat paint.
And now there is no problem even with the perimeter seal, this part is by the way the most difficult part of the whole dome, se my construction page to see why.
With the dome done I turned to the woodwork, this has to be secured to if it is to stand rain or snow.
First I put on a layer of paint then a layer of epoxy sealing the wood and paintwork and making it a perfect painted surface.
And voila! The dome won’t get wet and the stucco prevents it from visiting my neighbors it also became so sturdy that my kids can stand on top of it without any risk of breaking it.