Man hole

[noseall]

we have used precast concrete lintels in the past, in order to reduce the size of an i.c. aperture. double them up to be sure.

 

[diycooper]

Dont understand how to do it that way this is my first time doing one.

Only just figured out what way to do it.

 

[diycooper]

I need a 500mm x 660mm cover.

If i go and get the cover from the building yard the 460m x 610mm
i need to make up 50mm which would be 25mm on either side.

can you get 25mm lintels or could i use timber?

 

[marshman]

lower your biscut hight to allow for brick course / courses
then corbel the bricks in to hole size needed.

 

[diycooper]

Could i use 2 flags one on each side of the hole in the slab and position them to the right size i need covering the hole?

 

[marshman]

I suppose you could if they are 18 inches wide you could cut them down the middle and bed them around on 4&1 you need to support all 4 sides of your new frame. wet your concrete before you lay your mortar
and the under-side of your flags before bedding them.
incidentally how thick are your flags ? I hope they're at least 40mm.

 

[diycooper]

They are 30mm thick.
What do i need 4 x 1 for i was going to just bed them onto of the original concrete slab.

Or i could make a frame inside the hole to the size of my man hole tray then pour concrete in till it sets.

Do you think that would work better

 

[marshman]

4&1 mortar mix. you would be best to lower the hight of your biscut
then use engineering bricks.

Or i could make a frame *inside* the hole to the size of my man hole tray then pour concrete in till it sets. [/u]

you could then at some stage you lid an all could drop down through the hole.
if you want to bodge it get some 10x100mm flat steel and weld it into
a frame to reduce your hole size.

 

[noseall]

lower your biscut hight to allow for brick course / courses
then corbel the bricks in to hole size needed.

this is by far and away the most sensible and logical answer so far.

 

[diycooper]

What does corbel mean though.

 

[noseall]

brick corbelling or oversailing is where bricks are laid slightly off set of one another instead of directly on top and plumb.

this allows a wall to be stagger built on a different plain to plumb, for decorative or practical usage.

 

[diycooper]

Briliant, i was thinking of that originally but as i am have never done this before i didnt know if it would be strong.

 

[noseall]

it will be strong but don't get greedy with the overlap.

 

[diycooper]

Excellent i'm sorted know know exactly what i doing thx for help people, appreciate it.

 

[diycooper]

I have sorted the man hole out now but what i need to know now is i have a man hole in my back and one in the front and a pipe runs underneath the house to join them. Is it ok to have a drain pipe underneath your house.