Timber Mock Sash Windows

The character of a traditional sliding sash, in timber, on a casement mechanism. Ideal where a property does not have the depth for a genuine sliding sash.

Designed, supplied and fitted by our own team across Surrey, Berkshire, North Hampshire, Middlesex and West Sussex. Showroom in Guildford.

Mock sash windows look like a traditional vertical sliding sash, but open like a casement: a fixed pane and a single tilting sash rather than two panels that slide. In timber, that gives you a genuinely traditional material with a genuinely practical mechanism.

From £3,100 per window, supplied and fitted, including VAT.*

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mock sash double glazed windows on a house

From £3,100 per window*

Based on a 1200 x 1200mm window, fitted, inc VAT, based on 4 windows fitted

A rated

Ask your surveyor for the U-value

PAS 24 available

Enhanced security, specified on any window

Looks like a sash, opens like a casement

No sliding mechanism to maintain

8 to 10 weeks

Order to installation, then 1 to 2 days on site

10 year guarantee

Insurance backed as standard, plus your FENSA certificate

White uPVC sash windows fitted to a period house front in Surrey mock sash double glazed windows on a house mocksash green door white mock sash mocksash Mock Sash house white upvc mock sash Double glazed mock Sash Windows in Cream mocksash mock sash

What timber mock sash windows cost

From £3,100 per window, supplied and fitted, including VAT.*

Most window companies will not put a number on a page. We will, because you need one before you invite anyone into your house.

Prices are indicative. Every opening is different, and your quotation is the accurate number, free of charge.

Spread the cost

Your payment can be spread monthly over a term of up to 10 years.** Finance is provided by Dopple and you apply through our finance portal. A small deposit is due on order, the balance on completion.

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Double glazed mock Sash Windows in Cream

How long it takes

Stage How long
Enquiry to home visit As little as 2 working days
Home visit to quotation 2 working days, up to 5 for specialist items
Order to technical survey Up to 10 working days
Order to installation Generally 8 to 10 weeks
Time on site Typically 1 to 2 days for a full house
Do you need to move out? No. You stay in the house throughout

Why quotes are valid for 14 days

Glass manufacturing is heavily energy dependent, so our costs move with energy prices. Rather than pad every quotation against a rise that may not happen, we quote the real number on the day. If it lapses, come back whenever you are ready and we will requote free of charge.

white mock sash

Why homeowners choose timber mock sash

You want a genuinely traditional material with a practical mechanism. Timber gives you the real material, mock sash gives you a tilting casement sash instead of a sliding mechanism to maintain.

You want it where a real sliding sash will not fit. Genuine sliding sashes need depth in the frame that not every property has.

You want period character at a lower cost than a traditional sliding sash. Mock sash keeps the look without the expense of the authentic mechanism.

You want a wide choice of finishes. 34 colours, including 8 woodgrains, to match a period elevation properly.

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mocksash

Timber mock sash window security

Every timber mock sash window can be specified to PAS 24, the enhanced security standard that Building Regulations require on new homes. Tell your surveyor if security is a priority for you and we will specify accordingly.

  • Can be specified to PAS 24, the enhanced security standard used by Building Regulations
  • Reinforced frames as standard
  • Internal beading, so the glazing cannot be accessed from outside
  • Multipoint locking systems
  • Lockable handles

Tell your surveyor if security is a priority and we will specify accordingly.

Expertise You Can Trust

Proudly serving Surrey since 1972, we’re a family-run glazing company offering quality windows, doors, conservatories, and bespoke glass solutions. Whether you’re upgrading your home’s look with double glazing, choosing a new front door, or planning a unique orangery, our team is here to bring your vision to life.

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Mock sash or traditional sliding sash?

Both give you the classic sash look, in the same material. The difference is how they open, and what your property can take.

Mock sash Traditional sliding sash uPVC
How it opens Fixed pane, one tilting sash, like a casement Two panels that slide vertically
Frame depth needed Standard casement depth Deeper frame required for the sliding mechanism
Maintenance Low, no sliding mechanism to maintain Sash cords, weights or spiral balances need occasional attention
Look Close match to a traditional timber sash from the outside The genuine period mechanism
Price More accessible Higher

Mock sash is the practical choice where the depth is not there for a real sliding sash, or where budget matters more than having the authentic mechanism. Bring a photo of your elevation to the Guildford showroom and we will tell you honestly which suits your house.

Planning your next project? Check if we cover your area.

Sheerwater Glass proudly provides window and door installations, repairs, and glazing services throughout Surrey and the surrounding areas from our showrooms in Guildford and Woking.

To find out whether we cover your area, simply click the button below and check your postcode.

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Styles and configurations

A fixed pane with a single top or side hung tilting sash, styled to echo a traditional two over two or six over six sliding sash. Georgian bars are available to complete the period look. Trickle vents fitted where Building Regulations require them.

Farrow & Ball

Farrow & Ball Colour Chart

Timber mock sash specification

Window Energy Rating A
U-value Ask your surveyor
Species and construction To be confirmed
Finish To be confirmed
Configuration Fixed pane with a single tilting sash
Frame depth To be confirmed
Maximum sash size Ask your surveyor
Maximum sash, top hung 1200 x 1200mm
Security Can be specified to PAS 24. Reinforced frames, internal beading, multipoint locking, lockable handles
Security Can be specified to PAS 24. Trojan shootbolt locking to BS7950
Colours and finishes 34, including 8 woodgrains
Guarantee 10 years on frames, glass units and workmanship. 5 years on moving parts and hardware

Hear from our customers

“Nick from Sheerwater Glass just finished fitting my windows – Great service, quick, efficient and very friendly. Definitely recommend.”

Deborah Proudfoot
Sheerwater Glass Customer

Your Glass Options

Option What it does Standard or upgrade
Argon fill Better insulation than air Standard
Low emissivity coating Reflects heat back into the room Standard
Warm edge spacer bar Cuts heat loss and condensation at the edge of the glass Standard
Toughened safety glass Required by Building Regulations in some positions. We will tell you where Where required
Acoustic glass Worth it on a main road, but only ever as good as the fabric of the building around it. Ask your adviser Upgrade
Laminated security glass Holds together if broken Upgrade
Obscure and patterned Bathrooms and overlooked windows Upgrade
Leaded and Georgian bar Period elevations and conservation areas Upgrade
Upgraded thermal unit Improves the U-value of the whole window Upgrade
Triple glazing Best performance, heaviest units. Available on selected frames Upgrade

Your guarantee

Frames, glass units and workmanship 10 years
Moving parts and hardware 5 years
Insurance backed guarantee QANW, as standard
FENSA certificate Issued automatically on qualifying installations

The insurance backed part matters: your cover survives even if we are not here to honour it, and we provide it even on installations that do not qualify for FENSA. Most local companies do not.

Questions we get asked

What is the difference between a mock sash and a real sliding sash?

A mock sash has a fixed pane and a single sash that tilts open, like a casement window. A traditional sliding sash has two panels that slide vertically past each other. Mock sash suits properties that do not have the frame depth a genuine sliding sash needs.

Are timber mock sash windows secure?

Yes. Every window can be specified to PAS 24, the enhanced security standard Building Regulations require on new homes.

Do I need planning permission?

Usually not, but you might if your house is listed or sits in a conservation area, and there are around 200 of those in Surrey. Mock sash is often chosen precisely because it keeps a period look in these areas. We will flag it at survey if we think you are affected.

Will I get a FENSA certificate?

Yes, automatically, on every installation that qualifies. You will need it when you sell the house.

Can I buy the windows without installation?

Yes. We supply only if you are arranging your own fitting.

Ready to get a quote?

You’ll speak to a real person, not a call centre. We’ll talk you through options, no pressure.

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Pricing, finance and page notes

* Prices are indicative starting prices, reviewed regularly. They are based on a 1200 x 1200mm window in white with one side hung opener, a fanlight and a fixed pane below, supplied and fitted including VAT, and an order of four windows to the same property. Colours and woodgrain finishes cost more.

** Finance is provided by Dopple, not by Sheerwater Glass. Sheerwater Glass Ltd is an Introducer Appointed Representative of Social Money Ltd, trading as Dopple, which is authorised and regulated by the Financial Conduct Authority, firm reference number 675283. We introduce you to Dopple and we do not lend or give credit advice. Applications are made through our finance portal and all lending is subject to status and affordability. Dopple provides the rate, the term options and a representative example before you apply.

Specifications vary by window style, so a figure given here for a timber mock sash window may not apply to another style, size or material. What governs your installation is the specification in your written quotation and signed contract. If a particular figure matters to your decision, ask your surveyor and we will put it in writing.