Sash Window Restoration and Repair
Draughtproofing Double Glazing New Joinery
Mill House Window Workshop
Creating a workable balance between the conservation of period buildings and the provision of energy efficient and comfortable homes has long been an issue for Architects, Planners, Conservation Officers and home owners.
Slimline units are constructed using narrower cavities between the panes of glass than standard double glazing units, and perfectly replicate the appearance and features of single glazing on original timber windows.
By doing so this allows a home owner to gain all the thermal and sound benefits of sash window double glazing without compromising the character, charm or value of their property.
From the exterior and the interior (unless you look very closely), you can’t tell that the windows have double glazing fitted.
With standard double glazing it is immediately apparent that the glass has been changed which is detrimental to the character of the property as well as its value.
The thermal efficiency benefits of slimline double-glazing can now be even better than standard double-glazing, achieving U-values (the term used to measure thermal efficiency) of as low as 1.2 on a 6mm gas-filled cavity, depending on the type of gas fill used.
The reduction of heat loss through the glass is up to 77 percent as when compared against single glazing and it is possible on some windows to use slimline units to achieve the new Part L building regulations for thermal efficiency.
Slimline sash window glazing units are manufactured using a combination of the very highest specification materials available.
As standard, Slimline units include Planitherm Total Plus soft coat glass as its Low E pane, which is more thermally efficient than traditional hardcoated glass, such as K glass, and it also does not carry the same amount of colour.
With slimline units being available with either a 4mm or 6mm cavity, they are available from only 11mm thick with a perimeter seal width of from only 7mm.
This enables homeowners to benefit enormously from energy efficient double glazing, whilst replicating the original design of their windows including the narrow glazing bars so important to maintaining a truly authentic appearance.
Units can be installed to both new and restored traditional windows and doors, whilst allowing for glazing bars as narrow as 21mm, with putty line detailing to match the existing.
These high performance units are produced using the latest technology warm edge spacer bars in a choice of colours, ensuring they are as thermally efficient as possible and can produce centre pane U values from just 1.9 uv on a 4mm gas filled cavity, to as low as 1.2 uv on a 6mm gas filled cavity, depending upon the type of gas fill used.
TIMBALITE SLIMLINE DOUBLE GLAZED UNITS REQUIRE:
• A minimum 8.5mm rebate depth
• A minimum 20mm rebate width
• A minimum 21mm wide glazing bar
All Timbalite double glazed units carry a 5 year.
• Conform to BS EN 1279/Part 2, Part 3
• Can achieve as low as 1.2 U value
• Can meet new Document L building regulations, subject to confirmation via “whole window” calculator tool
• Can be supplied with low E, Restoration (reproduction Crown), toughened, laminated or may other special types of glass.
Top 10 reasons for choosing using slimline sash window double-glazing over standard double-glazing for conservation, listed and period properties:
1. PERFECT REPLICATION AND AUTHENTICITY - Slimline units perfectly replicate the appearance and features of single glazing on original timber or period windows and by doing so allows a home owner to gain all the thermal and sound benefits of double glazing without compromising the character, charm or value of their property. From the exterior and the interior (unless you look very closely), you can't tell that the windows have double-glazing fitted. With standard double glazing it is immediately apparent that the glass has been changed which is detrimental to the character of the property as well as its value.
2. NO DOUBLE REFLECTION - Slimline units do not produce the unnatural "double reflection" or “distorted reflection” that is sometimes seen when you use standard double glazing.
3. VARIABLE REFLECTIVE ANGLE - Each slimline unit is fitted on a bedding putty compound which gives each pane a very slightly different reflective angle of light to any onlooker which is a key factor that helps to maintain the originally and character of any period property façade. Standard double glazing, as it is constructed as one glass unit with applied mouldings to replicate the glazing bars gives off the same reflective angle from each and every pane which can look modern and unnatural.
4. PUTTY LINE BEADS - Slimline units are glazed into position using a 9mm x 9mm putty line glazing bead which matches the original design and proportions of the original putty bead used for single glazing as opposed to the larger glazing beads required by standard double glazing that change the proportions and section sizes of the windows.
5. THERMAL EFFICIENCY - The thermal efficiency benefits of slimline sash window double-glazing can now be even better than standard double-glazing, achieving U-values (the term used to measure thermal efficiency) of as low as 1.2 on a 6mm gas-filled cavity, depending on the type of gas fill used. The reduction of heat loss through the glass is up to 77 per cent as when compared against single glazing and it is possible on some windows to use slimline units to achieve the new Part L building regulations for thermal efficiency.
6. FUTURE REPLACEMENT - Replacing the individual panes of slimline glazing is easy should the need ever arise to replace a cracked or damaged pane. Standard double-glazing units use applied glazing bars to try and achieve a “period look” by sticking timber mouldings to both sides of the glass. This effectively means that, should a window ever break, then the glass to the whole window will need to be replaced and this will require the services of both a glazier to replace the glass and a skilled joiner to replicate and replace the timber beads to achieve a satisfactory replacement. With slimline double-glazing, as with single glazing, you would just need to replace the broken pane, making the job a lot simpler.
7. APPROVAL & SUPPORT - Slimline sash window double-glazing is now gaining favour and acceptance over standard double glazing from architects, contractors, conservation officers and planning officers around the country for replacing single glazing with slimline double-glazing if you live in a period, listed or conservation/heritage property.
8. REDUCED COST - The cost differential between slimline units and standard units has reduced greatly over recent years.
9. AVAILABILITY & CHOICE - The availability of slimline glazing is now much wider and joiners are more used to fitting it. It is the best solution for traditional-looking windows with improved thermal efficiency and there is a choice of glass finishes from modern satin through to more traditional fleur finishes to match original details.
10. A COMPLETE SOLUTION - Slimline double-glazing is suitable for many types of doors and windows, including sash windows, box sash windows, casement windows, sliding and bi-fold doors. They can be fitted into new joinery elements or can, unlike standard units be possibly retrofitted into the existing original windows.
Further information on the Glazing Products we use