How to deal with external heating/gas plywood pipe box

frankled

Not sure what to do here- somebody might be able to offer some advice or inspiration!

Due to a couple of issues when we got our house refurbished prior to moving in eight years ago, we have this unsightly godawful and outright wrong pipe box beside our back door. It houses central heating pipes and a gas pipe that exit the house below floor level in order to return inside at boiler level (I know, I'm well aware it is awful and not the way it should've been done).

We're getting our garden done in the coming weeks. This involves outdoor porcelain tiles and accompanying subbase etc. which will inevitably bring the finished patio above the bottom of the box. As I see it, below are my options for how to deal with this:

1. Internally, take up some kitchen tiles and possibly remove the kitchen unit, kango into the floor and around the pipes, and re-route them up to the boiler internally. This would be great, only I am loathe to this option- it is big, messy, and I just don't have time for it.
2. Build a pretty box (treated timber or some sort of composite option) AROUND this existing plywood box when the garden is done.

I'm leaning towards option #2. However, this doesn't solve for me the problem that the bottom of the box will still be below patio height. Added to that, I removed the box front yesterday (pictured) and noticed that a part of the frame has finally rotted (I'm really surprised this didn't happen sooner).

Insulation is obviously important here. I'm either going to have to replace the rotted piece and build a nice pretty box, dealing with the oddity of the paving being installed AROUND the plywood box, or, do something a little more permanent. What I'm thinking here is (option #3) insulate (using what, other than pipe insulation and expanding foam, as is currently in-place), and box-in (at the bottom at least) using cement board.

Wondering if anybody has any thoughts on this, if there's a better way of doing this job? Can pipes sit within expanding foam/insulation outside, below (but nearly level with) a patio?

The Continental Op

A neighbor has a extension that included a steel I beam on the outside corner of one wall. They put a wooden frame around it and clad that with cement board then plastered over it.

If I was keeping that I'd probably do the same but make it a bit deeper so there is room for some more insulation.

Calahonda52

If the insulation gets wet it's useless.

How far up the step on the left will the finished tiles be?

frankled

Not sure yet, awaiting the patio guy's say-so on that.

I've since gotten rid of all the timber, leaving insulation etc. My plan from here is to mortar in the bottom and I will likely protect the bottom of the box with waterproof membrane. Then, I'm thinking of building a neat box made of composite decking joists and cement board. I can then mortar in gaps etc., and once the patio is done, build a box/unit around the whole thing that can be clad in something half decent e.g. treated timber or cladding of some sort, such as composite stuff.

DublinDilbert

If the timber is not completely rotten, i would cover the lot with some UPVC facia, I've done similar before. You might need so flashing or silicone to seal it to the wall. As the fascia is a right angle, it will sit lovely on top of that timber and should look neat enough.

https://www.goodwins.ie/products/Fascia-Board-White-PVC-225mm-x-5mtr.html?filter_set[]=16,1227,1376

Calahonda52

top of box needs to slope out a bit to deflect rain from splashing wall above the dpc

frankled

https://www.boards.ie/discussion/comment/123466242#Comment_123466242

Thanks. For the purposes of accomodating the patio being installed at the bottom I've opted for replacing the existing timber box with a new one made out of composite joists and cement board. The cement board will accomodate the patio better I think, however the company doing this work finish it at ground level. I chose the joists for durability.

https://www.boards.ie/discussion/comment/123469698#Comment_123469698

Great point- I'll give the cement board box a slight slope out. As it happens, once my garden is done I am likely going to cover the box entirely with a small (protruding only 6-8 inches from the house I'd say) unit that will make the thing look a little prettier, so to speak. I will slope the roof of this too for deflection also.

Thanks all- appreciate the input.