Garden walkable hole cover

[topmarx]

Hello

I am doing landscaping and have a section of the garden that is just off a tiled patio, the goal is to put artificial turf down so it can be used as a BBQ area. The challenge is that in the far right corner is all the plumbing and water mains, inc sewerage access. The other challenge is that these pipes are probably 700mm below the patio ground level, raising all these is expensive.

The thinking is to build a retaining wall, rectangle around the water/sewer mains, either using sleepers, or bricks as I have a load of bricks left over from a recent renovation. This will create a 900mm x 1700mm rectangle. The idea is then to fill this section of the garden with soil so that it is just a simple small step down from the patio.  

So the remaining challenge I have is how to cover the rectangle retaining hole. I want to cover it so that it can be walked on and ideally covered with artificial grass like the rest of this section so it blends in, and hides the access to the sewerage system.

I am looking at two options:

Finding a galvanised mesh grate, but it is difficult to find the required 900mm x 1700mm size, and having a custom grate build looks very expensive. I am also looking at resin/fibreglass options but not having much luck.

The other is to build from wood timber, having slats going from the outer edge to the edge of the bricks, and then slats going the other way, from internal edge to edge, so the wood grate sits onto the bricks.

Looking for any help on finding pre-building grate options, else building a grate?

Thanks Marc

[Jewelleryrescue]

Hi @topmarx 

A good  product to use in your situation is  Light weight durafloor  Cement fibre sheeting 

How  much lighter than regular cement sheeting actual weights  not meantioned.

You may need a timber frame under it to then sit on your brick work and it may be advisable to make the cover in sections as 1700mm is a long span for any cover could be awkard and heavy.

I might also consider using red  or yellow tounge flooring if under coated and  paint sealed will withstand weather conditions as long as  paint holds  And easier to tack  artificial  lawn to. being  timber.

Ps  a forever fix Go with bricks I would double brick it and also put in retaining wall ag lines and gravel over ag line inside the brick wall dirt side.

They are allready at a natural  ground level the services.  And you are  making a pit of sorts so why not channel the Ag line and make a water exit point from inside the pit on the down hill  exit point for all waters. 

Hope this  helps

[JacobZ]

Hi Marc (@topmarx),

A warm welcome to the Bunnings Workshop and thank you for your question.

It sounds like an interesting project that I'd be happy to assist with. 

Is it possible to get some photos of the space just to clarify what we are looking at? 

This will help our members see what we're working with and offer their best advice based on the specific circumstances of your project. Let me know if you need a hand uploading images, I'm happy to help if required.

As @Jewelleryrescue has mentioned, 1700mm is quite a span, so whatever you go with will need to be capable of spanning that distance while supporting weight from above. 

A custom-fabricated steel grate could be a good option assuming it is engineered to the standard required to span this distance. Unfortunately, I am not aware of prefabricated options that would suit this purpose.

Timber is likely your best option for D.I.Y. as you would essentially just be building a deck that is attached to brick piers. You could build a frame out of 190 x 45mm Outdoor Framing H3 Treated Pine, which is capable of spanning 1800mm while acting as a bearer. You could then use decking boards or James Hardie 2700 x 600 x 19mm Secura Exterior Flooring as a surface material before laying your artificial turf over the top.

If it needs to be removable for access, we would need to tweak the design to suit. If this is the case, please let me know and I can provide some guidance.

Allow me to tag @Nailbag, @Dave-1 and @TedBear for their thoughts.

Let me know what you think.

Jacob

[Dave-1]

Afternoon @topmarx 

Mmmm I am having a little trouble picturing your yard and area you want to retain? lay artifical turf plus your services and where they are.

Is there any chance of a few photos of the area overall, the pit area? and your services?

Will wait and have a think about the area.

Dave

[Nailbag]

Hi @topmarx 

As an easement, it legally shouldn't be covered at all. However you will get away with something that can be quickly and easily removable. And as per your requirements, strong and safe enough to walk on long term.

Personally I would be going with a metal grate frame with a mesh overlay. This will allow water from your artificial turf to weep through without pooling on the surface. I am sure if you spend the time researching and shopping around that you will find someone who can do this affordably. You just need someone is a steel fabricator, who might even make gates etc. Its doesn't have to be a pretty finish just functional.

Nailbag