Clarification on "combined fall" - Planning for patio

[rushd]

IP: that is true, the width of intend paved area is nearly 4m.

mickg : so only a minimum fall is required for the drainage, but it's still a cross-fall. how shallow could it be?
1:100? or could it be shallower, eg 1:150?

[mickg]

yeah its still a cross fall

1:150 would be approx 25mm fall in the length of the drainage channels from the corner of the conservatory to the outlet on the corner of the house, this would be enough to disperse the water into the drain

you need to bed the channel flush to the house brickwork so it lines up with the existing drain what is below the downspout connection

[rushd]

i'm not bringing the paved area up to the house as it wouldn't be used/necessary. it's in permanent shade!
i'm going to put steps in front of back door and french doors, and the paving will start from these points.

encouraged that you state that the drainage channels will work at a shallower gradient. that's the ideal solution really. as long as there is enough fall to make the water move away...... i was worried that if it wasn't laid at something like 1:80 that it might overflow or backup. i wouldn't be happy!

is 1:150 defo ok?

[irishpaving]

Dont understand what you mean about a feature of the m/h. You need to set them in with your paving.

Are you using an edging around the perimeter of the area

[rushd]

i am going to edge with blocks, as per block paving. so the drainage channel will be set into the edging blocks.

i think the manhole is too high to be covered, so perhaps i'll brick around it and we'll put a plant on it etc

but i was hoping to hide/cover the ICs. Can they be cut down to a lower height?

[mickg]

is 1:150 defo ok?

yes it is, water will always take the path of least resistance which in this case is towards the outlet what you have installed in the drainage channel


the manhole cover will be sat on top of plastic raising pieces what form the sides to the manhole, its very easy to cut these down in height by using a 4" or 5" angle grinder whilst still in situ

clear the earth from around it and mark height you would like the finished height to be (which is the same height as your patio) making sure you have deducted the depth of the manhole cover and cut this surplus off and place the manhole cover back on top

its that simple and will look a lot better being the same height as the finished patio paving

the two smaller inspection chambers are there for a reason and its not advisable to cover these over as you need access to your drains if they ever get blocked

[rushd]

thanks mick

re: the big metal manhole
how do i get the lid off? is there a special tool that i need?
there must be a frame for the lid? does this simply sit on the top of the plastic raising pieces?
i presume that i have to take the lid off to expose the plastic spacers? i do have a mini-grinder so hopefully that would be up to the job.
it would be nice to make it less of an eye-sore.


re :inspection chambers
i was wondering if i could lower them and bed a loose slab over them, which could be lifted as&when required. but from your response i guess this is frowned upon.
could i atleast cut them down a bit to sure they are flush if required?


perhaps these are queries for another topic?

thanks for your advice re: falls.
much appreciated.

[mickg]

scrape the soil away what is touching the plastic frame that the metal cover is sat in and just lift it all off in one

its that simple

the two smaller inspection chamber covers will be the same, the lid is screwed into a outer frame what will be pushed onto a plastic raising piece what forms the inspection chamber, the outer frame will have a seal what makes the chamber air tight so you will have to rock it backwards and forwards whilst lifting at the same time and it too should come off all in one

you will have to purchase a raising piece as looking at the photos these covers are lower than the finished height of your patio, its difficult to see what you would need from the photo you posted but if you remove the cover and do a close up photo of the IC it will give us a better indication what you will require

[rushd]

thanks again mick

i'll update as i go along

[seanandruby]

re :inspection chambers
i was wondering if i could lower them and bed a loose slab over them, which could be lifted as&when required. but from your response i guess this is frowned upon.
could i atleast cut them down a bit to sure they are flush if required
much appreciated.

Yes it,s "frowned upon." Never cover anything that will need access to it.

[Mikey_C]

you want to put recess trays on all three as shown here

[rushd]

update on my project... drainage cover queries

took the frame off the top of the 'big circular' IC and measured the diameter of the chamber and i make it 49cm. the recess cover i have purchased is 45x60. ie. the frame of the recess cover doesn't fit over the diameter of the chamber....

it seems that my circular chamber diameter of 49-50cm is not standard?

what would be the best course of action?
1) butcher the chamber and seal it with concrete? (i don't like the thought of this!)
2) buy another cover?
3) am i missing something?


Also, I am working towards putting recess trays over the two small ICs, but i need to reduce the height of their chambers. is there are minimum level that I can reduce their height to as one of the ICs in particular is already shallow...as it takes the kitchen waste to the 'biggie'


thanks in advance

[rushd]

bump

[rushd]

started a new topic for my new question