Drive manhole covers-best way forward to replace.

anotherquestion

Hi there folks,

The two drive manhole covers (taking kitchen waste and sewer out from house) need replacing rectangular size of 650x500, but can't get that size any more. Am I right in thinking that 600x600 would be the best option to buy, with a little modifying to cover that 50mm space?

Obviously new trays would have to be fitted, does the installer just cut out the indent to fit them level in drive with a kango or other method.

Also as regards load (one will be in back garden) I believe its 2.5, 5 and 10 tones, would 5 be enough for both drive and back garden or do I need more?

Thanks a lot for any advice.

Eldi_Dos

Hi,
 Regarding the size of cover you need ,the best way to find out is lift the cover (lid) and see what size of chamber or shaft is being covered.
ie; you need to know the width of a gap before deciding what to bridge it with.

The normal replacement procedure is to work out the width of the flange on the frame then cut the surface with a stihl saw, although a angle grinder would do in a domestic setting.Break out the material holding frame in place, in a domestic setting a hammer and chisel would suffice but a professional might use powered tool for that.

Once frame is free remove the cover (lid) and frame, tidy up the surfaces and work out your depths, put in your mortar or compound and adjust level of frame, with some shims if need be. Let the mortar or compound set for a while before putting lid back on.

With the lid on the driveway if your vehicle straddles the cover you are good to go but if you drive over the lid best to leave for a minimum of 72 hours but preferably a week before putting vehicle across it.

It is quite a easy DIY job although with a drive appearance is important, I would say it is worth getting a professional to do it.

stuart45

Is this DIY, or are you getting someone in?

Section62

What kind of surface is surrounding the driveway and back garden covers?

anotherquestion

Thanks for replies, Yes I am getting someone in to do it, Its unfortunately way beyond my ability. Its a tarmac drive though not in perfect condition as its over 30 years old. Again the old size of lid is 650x500, no longer available, so I think nearest size will be 600x600  cover up that 50mm gap somehow, new trays fitted as well, what load do you think I might need as I need two done one in garden (tarmac area as well) and one on driveway, which might have car going over it, .here are some pics. I know a joiner who says he can do it.

stuart45

That looks to me like a 600×450 would fit it.

anotherquestion

Well the lid size only at the moment is  650x500, so 500 is across, so if I was to take your above choice I think I would have openings to fill in on both sides, since present size is 650 longwise that's 50mm to fill in opening, and since present size lid is 500 across that again would be a 50mm opening to fill in, whereas if I pick a 600x600 that only a 50mm to fill in on one side with equivalent tray size.

If anyone can check if my reasoning make sense thanks.

Section62

anotherquestion said:

Well the lid size only at the moment is  650x500, so 500 is across, so if I was to take your above choice I think I would have openings to fill in on both sides, since present size is 650 longwise that's 50mm to fill in opening, and since present size lid is 500 across that again would be a 50mm opening to fill in, whereas if I pick a 600x600 that only a 50mm to fill in on one side with equivalent tray size.
...

You need to measure the brickwork opening rather than the size of the existing cover.  The internal dimensions of the inside of the frame of the new cover needs to be larger (say a minimum of 10mm each side) than the brickwork, so the frame is fully supported all round.

Slinky

We had a couple of covers on our drive. The drive company who replaced the concrete drive with tarmac sourced the covers and did the work. We had them done with tarmac set into the covers. If you're using professionals they should be used to knowing what needs to be done.

stuart45

anotherquestion said:

Well the lid size only at the moment is  650x500, so 500 is across, so if I was to take your above choice I think I would have openings to fill in on both sides, since present size is 650 longwise that's 50mm to fill in opening, and since present size lid is 500 across that again would be a 50mm opening to fill in, whereas if I pick a 600x600 that only a 50mm to fill in on one side with equivalent tray size.

If anyone can check if my reasoning make sense thanks.

When brick manhole were built, the internal measurements of the brickwork were often 2ftx18inches, or 600mmx450mm. That's a standard size for a lot of manholes. The frame was designed for the inside edge to be flush with the inside edge of the brickwork. The brickwork on your manhole looks to have about 25mm all round smaller than the frame, so it looks like it was built for a 600x450 frame.

anotherquestion

stuart45 said:

anotherquestion said:

Well the lid size only at the moment is  650x500, so 500 is across, so if I was to take your above choice I think I would have openings to fill in on both sides, since present size is 650 longwise that's 50mm to fill in opening, and since present size lid is 500 across that again would be a 50mm opening to fill in, whereas if I pick a 600x600 that only a 50mm to fill in on one side with equivalent tray size.

If anyone can check if my reasoning make sense thanks.

When brick manhole were built, the internal measurements of the brickwork were often 2ftx18inches, or 600mmx450mm. That's a standard size for a lot of manholes. The frame was designed for the inside edge to be flush with the inside edge of the brickwork. The brickwork on your manhole looks to have about 25mm all round smaller than the frame, so it looks like it was built for a 600x450 frame.

Thanks for that Stuart, do you think it might be an idea for me to get one of those covers 600x450, just lift the old lid and see if the tray of the new fits ok?

Dark at night here, but I think on lifting covers before that is actually pieces of timber around the top edges of actual manhole brickwork.