How to renew a manhole cover
Job Date 15/08/2011
This cast iron manhole cover probably had something dropped on it. That's the problem with cast iron, it shatters.
I think they look better than the galvanised ones though. I decided to use a 10 tonne rated cover as the 5 tonne rated ones looked a bit flimsy to me.
I think they look better than the galvanised ones though. I decided to use a 10 tonne rated cover as the 5 tonne rated ones looked a bit flimsy to me.
After removing the cover, rinse the walls of the manhole and disinfect it too.
I normally use jayes fluid mixed with water and thrown around the walls.
Now break out the concrete. Use goggles on your eyes for this and a paper mask. If a stone chip went in your mouth or eye it wouldn't be very nice!!
I normally use jayes fluid mixed with water and thrown around the walls.
Now break out the concrete. Use goggles on your eyes for this and a paper mask. If a stone chip went in your mouth or eye it wouldn't be very nice!!
Heres a tip....
In a deeper manhole, you will get some of the debris in the drain.
Make a pick up tool by screwing some old plastic half round gutter to the end of a length of wood as in the picture.
You can then lower this into the drain run and use a length of batten to push the debris onto it. This will make your job easier.
Leaving debris in the drain is likely to block it.
In a deeper manhole, you will get some of the debris in the drain.
Make a pick up tool by screwing some old plastic half round gutter to the end of a length of wood as in the picture.
You can then lower this into the drain run and use a length of batten to push the debris onto it. This will make your job easier.
Leaving debris in the drain is likely to block it.
I have used a piece of expanded metal to stop the debris going in the drain.
You need to break out the concrete from around the manhole. Take care not to drop it in.
Set the debris aside as you go
You need to break out the concrete from around the manhole. Take care not to drop it in.
Set the debris aside as you go
I decided to break it out the old fasioned way with my scutch chisel.
I have now removed the cover and cleaned up the bricks. This is now ready for receiving the concrete bed.
Mix up your sand and cement 3 sand to 1 cement powder .
Use sharp sand. The cement needs to be quite strong when used on externally on the floor.
Use sharp sand. The cement needs to be quite strong when used on externally on the floor.
Mix the sand and cement together dry. I always use a plastic bath for this.
I added some SBR to the water to enhance the bonding properties of the cement. This is worth doing where the cement gets very thin at the edges when feathering in and will prevent it lifting.
The cement should be quite firm.
I coated the edges with the SBR.
This part is not necessary here but does help the cement bond to the bricks.
I coated the edges with the SBR.
This part is not necessary here but does help the cement bond to the bricks.
Offer the frame to see where the edges are.
These are often very close or even slightly over the edges.
These are often very close or even slightly over the edges.
Hold something on the inside edge to stop it the muck from falling in and to give you a good edge.
Continue all the way round
Level the frame to the sides with a straight edge. do this in both directions to get the best level
Finish with a plastic or wooden float.
Use a brush dipped in water or SBR to feather into surrounding levels
Job Done!
Please check with your local water-board or building control to determine who owns the drains and ask if you need permission before working on drains.
They may want you to use specific materials and specify what you should do.
Please check with your local water-board or building control to determine who owns the drains and ask if you need permission before working on drains.
They may want you to use specific materials and specify what you should do.
Tools for the job.
Of course if you don't fancy trying this yourself, you can always ask BBS Building Services for a quote!!
This 'how to' was bought to you by Paul from BBS Building Services.
Of course if you don't fancy trying this yourself, you can always ask BBS Building Services for a quote!!
This 'how to' was bought to you by Paul from BBS Building Services.