I have to put a bay window of 240 with light of 120 I do not know the scheme to make its threshold. If you could sketch me with the odds it would be nice.
Attention, the construction of a threshold of Bay window especially of this size, implying the weight which it will have to support and the good sealing, would profit to be realized only by a professional.
However, there are concrete support pieces of different lengths, depending on the desired dimension, that can be used by the construction material dealers to allow you to install your bay window correctly.
We can not send you a dimensioned drawing, but you can make a reinforced concrete outsole 10/15 cm deep and about 20 cm wide.
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