SIPS Panels for Porch?

[GettingOnWithItAll]

SIPS panels are useful for professionals building whole houses, but are they any good for DIY on a small porch? I can ask the panel producers, but I suspect their advice will be biased, and a couple of hours searching the internet left me none the wiser.

I'm a competent DIYer and feel up to doing everything apart from brickwork (I've done it for gardens but just can't get mortar to behave) and the electrics (I'm very capable but not certified (don't believe my ex-wife)).

Details of the Idea.

I'm looking at a porch with one new wall, a roof, an entrance door and a window panel.

The images show my (North-facing) house on the right and my neighbour's porch on the left. Essentially, the previous owners agreed to have a joint build then pulled out, which explains why the party wall straddles the property dividing line and their roof overhangs our ground. I'm looking for a broadly similar porch to fill in the 1.2m x 2.1m floor plan, matching the brickwork and carrying the roof over.

I'm not expecting any admin/legal issues. The neighbours are happy and will give formal party wall consent. The house has had no development so the porch is well within permitted development limits. I'm keeping the old front door in place so, in theory at least, I can be relaxed about Building Regs.

Why am I dithering?

Moving past the obvious answer of my being indecisive (but am I really?), I'm unimpressed by my 2 main options of a single skin brick structure (cold in winter, so of limited use for storage of coats etc, and often picked up on sale surveys as 'a problem') and a double skin insulated structure (300+mm thick, so takes out a big chunk of the available 1.2m), and SIPS panels with a brick slip outer covering might offer insulation without taking up too much space.

Furthermore , it all seems a lot of work for not much space so I'm still open to forgetting the porch, fitting a modern composite front door and building a larger door step with drainage (the area gets flooded easily), possibly also replacing the old concrete overhang with a roof to match next door's.

 

[pilsbury]

If I were you, I’d copy the neighbours porch mirrored on your property. I might be corrected, but you don’t have to go full 300mm cavity wall for a porch if you have a front door still going to the house.

As for SIPS, I briefly investigated this for my extension. Worked out a whole lot more expensive than brick/block. Seems to come into its own when doing big full house builds, not little jobs.

 

[^woody^]

If I were you, I’d copy the neighbours porch mirrored on your property. I might be corrected, but you don’t have to go full 300mm cavity wall for a porch if you have a front door still going to the house.

As for SIPS, I briefly investigated this for my extension. Worked out a whole lot more expensive than brick/block. Seems to come into its own when doing big full house builds, not little jobs.

You seem to talk more sense when you've had a few.

 

[GettingOnWithItAll]

Thanks.

I'd pencilled in copying the neighbours theme, albeit with a free hand I'd consider some big changes. I'd prefer the door against my RH wall, not offset using a panel, I dislike the PVC half-height panel as it just looks cheap (I'd have a brick half-height w)all with window, and the bricks above the door are a pain, requiring a lintel as they do), and I dislike the steep roof (I'd prefer lower and shallower). What I'd like to do and what will work may be 2 different things though.

I don't need a 300mm double cavity. My issue is that a single skin wall, as my neighbours have, is inadequate for using a porch in winter for anything other than macs, wellies and the like; coats and shoes just get cold and damp. Doing a reasonable job of a single skin wall (say 110mm brick, 50mm insulation, 50mm battens, 20mm plasterboard & skim) gives me 240mm, a fifth of the floor width, and a lot of work for not much gain.

Although the panels would be relatively cheap as I save paying a brickie, but the cladding and all the rest do indeed make it relatively expensive. That said, the area is small so a big % difference is still not a lot of money.

If I'm not going to worry about using it then I could build a roof and use infill PVCU/composite door and panels such as the images. Clearly they're more expensive than not having an infill and I have to worry about clashing with the neighbour's porch, but I'd save the cost and work replacing the front door. The thumbnails show some ideas. The extra cost over doing the minimum might be justified if the space is useful for future owners, for example as pushchair storage.

Decisions, decisions. And then there's having to please my wife (eg she wants a blue door). . . .