Welcome to I-Sash Windows

we specialise in the renovation, restoration and performance upgrading of sash windows

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What makes us tick.


From historic period buildings to old style tenement buildings, sash windows contribute greatly to the appearance of these beautiful old building but require a great deal of maintenance. At isashWindows, we have the skills and expertise to restore any sash window to its former glory and bring a modern touch to provide greater performance and durability against.


Our craftsmen have over 25 years of experience between them to ensure that your project will be handled by the most knowledgeable and experienced in their field. We work with you every step of the way, from the evaluation of your current sash windows, to the free quotation based on your requirements and budget.  Whether it’s a standard overhaul, draught proofing, noise reduction or a new sash window manufactured to match your existing windows, we have the perfect solution.

The urge for good design is the same as the
urge to go on living.

Good design is good business.

What we do

Our Mission

As we offer a full repair replace and plastering service we will get your windows back to the original glory then agree with you a maintenance programe to ensure that you will only have to get the restoration done once then it is an ongoing project to ensure your windows always look and perform as they should


Sash Window Restoration Process includes


Remove beading & carefully remove top and bottom sashes

Assess condition of sill, box frame and external pointing

Remove excess paint from frame and effect repairs as necessary

Replace sash cords and service pulleys

Re-balance sash weights to ensure smooth operation of both top and bottom sashes

Assess condition of top and bottom sash

Renovate top & bottom sashes, planing off excess paint and repairing putty damage where necessary

Install concealed draft proof system

Prime all exposed woodwork and caulk beading leaving the window ready to decorate

Fit new centre catch, up-lifters, sash eye and window locks as per clients instructions

Full operational demonstration

Single Glazing

double glazing

Many choose to update their sash windows to double glazing, but this is not always possible. With help from our consultants, you'll be able to determine whether your windows can be upgraded to double glazed or be exact copies of the original single glazed. Our single glazed units are of the highest quality and with the addition of draught proofing and our unbeatable joinery skills, we're sure that you'll be satisfied..

Double glazing brings a multitude of benefits, including a sharp decrease in noise pollution with the correct glazing configuration , greater insulation and better security, and with i-Sash Windows, upgrading your sash windows to double glazing has never been so simple.


At isashWindows, our consultants are with you every step of the way, from determining if double glazing is suitable for your windows to the best approach in carrying out the upgrade.


There are two ways to upgrade to double glazed sash windows: renovating your existing windows or replacing the entire units. Your consultant will guide you through the entire process and will work with you to determine the best course of action depending on your existing windows and your budget..

sash window painting


The key to long lasting sash windows is good maintenance and painting forms a very important part of that. Professionally painted windows not only protects the timber but will give years of trouble free service.


Preparation is everything when it comes to a long lasting paint job, that is why we remove the old paint back to bare timbers, which gives a better result on the finished job. We use professional painters to carry out every job to ensure that every sash window is protected against the weather and finished to perfection. Almost any colour can be achieved and no further painting will be required for up to 6 - 12 years.

Flaking paint and failed Mastic seals are classic signs of sash windows which have not been properly maintained and have fallen into disrepair. At i-Sash Windows, we look beyond the decay to bring out the beauty underneath.


We believe that traditional sash windows can make any building look stunning and our aim is to being these beautiful windows into the twenty-first century. Our team are highly skilled and can repair sash windows in almost any condition. We pride ourselves on being able to offer the most cost effective solution to retain the character and value of your home.

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Contact Us

I02 Westcombe Hill








TeL: 020 3289 0413



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