Right.........
I am in the process of ordering steels as I am about to knock through an existing wall. At present this external wall leads onto a flat roof extension via a door, the plan is to open this are up fully. I have had the calcs done for the steels which are fine. Now, my problem arrises with the spec of the padstone to be inserted into the floor so that a vertical riser can bolt to it. The size of this padstone is 750 x 750 x 300 thick.
The building inspector has stated I dig down approximateley 700/800mm until i see the start of the external foundations and then call him out to check and once, happy I can fill to 300mm. The problem is once I pour a GEN 3 Cement, in effect make a 300mm thick padstone, what happens with the other 400mm? the vertical column is to fix via a base plate and anchor bolts to the padstone?
1. Do i cut out a 750 x 750 x 300 hole in the floor and lay DPM then pour a GEN 3 Mix (Not sure If I can mix this myself and if so what is the ratio) onto the DPM, fix the vertical riser with anchor bolts and then refill with wither ground and then screed of fill the remailing 400mm with the same mix?
also looking at the plan does this need to be cast on 2 stages as there will already be a foundation running down the middle, or would the ned padstone rest ontop of the existing foundation?
I have attached the image of the area in question.
cheers guys your feedback would be much appreciated!
View media item 50611 [/img]
I am in the process of ordering steels as I am about to knock through an existing wall. At present this external wall leads onto a flat roof extension via a door, the plan is to open this are up fully. I have had the calcs done for the steels which are fine. Now, my problem arrises with the spec of the padstone to be inserted into the floor so that a vertical riser can bolt to it. The size of this padstone is 750 x 750 x 300 thick.
The building inspector has stated I dig down approximateley 700/800mm until i see the start of the external foundations and then call him out to check and once, happy I can fill to 300mm. The problem is once I pour a GEN 3 Cement, in effect make a 300mm thick padstone, what happens with the other 400mm? the vertical column is to fix via a base plate and anchor bolts to the padstone?
1. Do i cut out a 750 x 750 x 300 hole in the floor and lay DPM then pour a GEN 3 Mix (Not sure If I can mix this myself and if so what is the ratio) onto the DPM, fix the vertical riser with anchor bolts and then refill with wither ground and then screed of fill the remailing 400mm with the same mix?
also looking at the plan does this need to be cast on 2 stages as there will already be a foundation running down the middle, or would the ned padstone rest ontop of the existing foundation?
I have attached the image of the area in question.
cheers guys your feedback would be much appreciated!
View media item 50611 [/img]