Timber Bay Windows
Bespoke timber bays to suit the house, not fight it
A bay window can make or break a room. Done right, it pulls in light, gives you extra space and actually suits the front of the property. Done badly, it leaks, rots and looks like an awkward bolt-on.
At JM Joinery we manufacture bespoke timber bay windows from our workshop in Callow, Herefordshire. We build new bay frames and replacement bays to match existing features – in casement or sash styles – designed to actually fit your opening and your house.
Supply only, or supply & fit within our installation area.
What we mean by “bay windows”
We deal with most typical bay types, including:
Angled / splayed bays – common on Victorian and 1930s houses
Square / box bays – flat front with 90° returns
Oriel-style bays – projecting bays at first floor level
Simple multi-part front bays – where you’ve got three or more window sections making up the bay
We can replace just the window frames and cills, or on some jobs work alongside your builder if the structure/roof/brickwork needs altering.
Why use JM Joinery for bay windows?
Made to measure – we build the bay to your actual angles and sizes, not a guessed standard.
Proper timber sections – sized for strength, insulation and looks, not just the minimum.
Casement or sash – we can match existing style through the rest of the house.
One complete unit – posts, cills, frames and mullions all designed together.
Supply only or supply & fit – we can manufacture for your installer, or handle the fitting within our radius.
Styles – casement and sash bay windows
We can match what you already have or upgrade while keeping the look:
Casement bay windows
Top-hung or side-hung casements.
Traditional or modern profiles.
Options for dummy sashes to keep sightlines consistent.
Sash bay windows
Traditional sliding sash look (subject to structure and design).
We’ll talk through cords/weights vs spring balances depending on space and spec.
Internal linings and architraves can be made to suit.
If the rest of the house is already upgraded in a particular style, we’ll aim to tie the bay in so it doesn’t look like a separate era.
Timber options
Materials depend on exposure, finish and budget:
Accoya – very stable and ideal for exposed fronts, dark colours and long service life.
Selected hardwoods – where a more natural timber look is wanted.
Quality softwood – for painted bays where budget matters but you still want proper joinery.
All timber is sourced from suppliers supporting sustainable forest management.
Glazing & performance
Glazing makes a big difference, especially with larger areas like bays:
Double glazing as standard for most bays.
Toughened safety glass where required by regs (low-level and critical locations).
Laminated glass available for additional security or acoustic performance.
Obscure glass for side lights or overlooked positions.
Glazing bars – traditional, slim or none, depending on the look you’re chasing.
We can provide U-value information for bay window units where needed for building control or spec.
Cills, posts & structure
A bay is more than just a few windows stuck together. Key details we deal with:
Continuous bay cills – accurately cut to your angles, properly dripped and weathered.
Intermediate posts / mullions – sized to carry the loads they need to, not flimsy stickwork.
Head beams / rails – where appropriate, to tie the frame together.
Junctions to existing walls – detailed for sensible sealing and support.
If the bay roof, brickwork or base needs work, your builder usually handles that – we’ll coordinate dimensions and interfaces.
Heritage & matching existing
If you’ve got a decent original bay that’s rotten, or a modern bay that looks wrong, we can:
Copy original details as closely as practical – mouldings, bar layouts, cill profiles.
Reduce bulky modern sightlines back to something that actually suits the house.
Work with photos, measurements and any old drawings you might have.
This is particularly useful on Victorian, Edwardian and 1930s properties where a cheap replacement bay has spoiled the front.
Finishes
We can supply your bay:
Fully factory painted – in standard whites/creams or custom colours.
Two-tone – one colour outside, another inside (subject to spec).
Primed only – ready for your decorator if you prefer to control final coats.
Factory finishing gives the best protection, especially on exposed fronts and larger bays that are awkward to paint once installed.
Supply Only or Supply & Fit
Supply Only
Ideal if you have a main contractor, window fitter or builder already on site.
Bay windows supplied as a unit or in sections, with cills, posts, frames and sashes.
Collection from our workshop in Callow, HR2 8BP (delivery can be discussed depending on size and location).
Supply & Fit
Available within roughly an hour’s drive of our workshop.
Careful removal of old frames as agreed.
New bay installed, packed, fixed and sealed properly to structure.
We’ll liaise with your builder if there are structural or plastering works tied in.
What we need to quote a bay window
To price a timber bay window properly, it helps if you can send:
Width and height of the bay, plus depth/projection if known.
Photos from inside and outside, including the cill, side returns and bay roof/base.
Whether it’s casement or sash, and if you want to match other windows.
A note on whether there are structural issues (subsidence, movement, rotten bases etc.).
Whether you want supply only or supply & fit, and your postcode.
We’ll then come back with a clear, itemised quote and a realistic lead time – no guesswork.
Planning a new or replacement timber bay window?
If your existing bay is rotten, ugly or just not doing the job:
Use the Get in touch form
Attach photos and rough sizes
Tell us whether it’s a straight replacement or part of a bigger project
We’ll give you straight advice on what’s sensible, what it will cost, and how best to tackle it – without the fluffy sales talk.