[Zippy]

This may not be a gardening project as such, but i know you are all a helpful bunch on here and I thought i would share my problem.

I have discovered that my rectangular manhole in the back yard was historically covered over by one course of block paving and then later by lightweight patio slabs.  This means that the manhole cover is about six inches below the surface at present.

I had to buy a new lid anyway as the old one had rusted under all the damp sand and stonework.

I have a mind to remove the lid, add two courses of bricks (or one course and a concrete top depending on what will bring me to the level I need), fit the new frame and lid and re-pave to finish.

Would that be easier than building a concrete casement to form a frame around the inspection hole?

Anything I should look out for - apart from falling in!

[John]

Anything I should look out for - apart from falling in!

A builder?

Sorry, couldn't resist it!

[Zippy]

A Cornish builder? I'll do it meself!

[Runwell-Steve]

I don't know exactly what type of manhole you have but you can normally buy risers which will just slot over the existing manhole where the lid goes now, and will raise the height of it.

Have a look in a decent Builders Merchant, they should have just what you need.

[muckshifter]

6" would be a tad tight for 2 courses of brickwork + frame,you could either lay 1 course and a split course +frame or a course on edge + frame.
How ever you tackle the job be sure to clean the manhole channel of debris and mortar spillage on completion.

[smud6ie]

What about constructing a ply box inside the existing pit up to the required level then another box of suitable wood the thickness of the wall  bigger than the inner and to the same height.Then you can fill with concrete and set the lid frame in it.then top with mortar.
smud6ie

[Zippy]

I like smud6ie's idea and it would be easier to level up against the existing patio level.

I was also thinking along those lines, thank you.

[Kleftiwallah]

If you go down the mould route, try and add a bit of reinforcing bar or heavy duty mesh to give added strength.   (I raised our manhole a few years ago),   Cheers,   Tony.

[Zippy]

A local builder advised just to replace the block paving over the manhole cover as it is and re-sit the patio slabs in sand and scrape the slabs and blocks back should we ever need to raise the manhole cover - ots not a problem that it is sizx inches below the patio so long as we (and any future dweller) know where it is.

[cannyfradock]

Zippy

If you want easy access to the manhole and have it blend in with the existing or new patio then you could buy a recess tray manhole cover......
 
 http://www.pavingexpert.com/images/trays/inStonePaving.jpg

They are not expensive and would suit your situation.

If 2 bricks takes your manhole cover too high then buy some cheap commons with a frog in them (shallow indent).....chip of the" frog" and use 1 and a half bricks to find the level required. If it's just foot traffic then use a stiff mortar mix and "bump up" the 1 course of bricks and lay the manhole cover on a heavy mortar bed

Terry

[Zippy]

Put lid back with plastic (compost bag) bag strips in the lid grooves to prevent rusting together, put block paving and patio slabs back on a bed of sand. Builder said it would be fine so long as we remeber where it is and leave a note for the next people if we ever move.

Crude but simple.

[2peasinapod]

I seem to remember it's against planning laws to cover an inspection cover.

whole or slpit brick is the best/easyest/quickest way to raise the frame

the recessed tray an infill to match is probably the best.

 HTH mark