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Double Glazed Sash Windows

Double Glazed Sash Windows

Preserve the charm of your original sash windows while dramatically improving energy efficiency.

With rising heating bills, many homeowners are looking for solutions that maximise the energy efficiency of their timber windows, whilst still retaining their authentic look and charm.

Our range of window energy saving measures includes replacement timber double glazed sashes and complete new windows that, in conjunction with our unique Ventrolla Perimeter Sealing System (VPSS), offers you a combination of high performance, comfort and style.

  • Reduced energy costs
  • Up to 30% improvement in energy efficiency
  • Slim discreet double glazed sashes
  • Easy future maintenance
  • 5 Year Guarantee

 

Ventrolla offers two Double Glazing Solutions

  • Replacement slim double glazed sashes, installed  into your existing sash box (window frame)
  • Complete new slim double glazed windows

Ventrolla’s primary double glazing solution is to replace the existing sashes with slim double glazed timber sashes, fitted into the existing box frame. This minimises the disruption and cost of redecorating, thus reducing the overall cost of the work. We can also manufacture and supply new double glazed windows that comply with Part L of the Building Regulations.

REPLACEMENT SASHES
Replacing original single glazed sliding sashes with bespoke double glazed sashes means you can get a double glazed solution without major disruption to the property.

TIMBER
The replacement sashes are manufactured from treated softwood, Accoya® or hardwood. Accoya®, our preferred choice of engineered timber, has a 50 year manufacturers’ warranty, and is an ultra-high performance all-natural wood. Made from certified sustainably grown timber, Accoya® has thermal properties and is naturally insulating. 

For further information, visit: www.accoya.com

GLAZING
We install slim glazing units, allowing us to manufacture sliding sashes using traditional carpentry methods, including solid glazing bars (instead of ones attached to the glass ), which help to retain the window’s authentic look and feel. Another main feature of the slim glazing unit is the reduced sightline of the spacer bar between the two panes of glass, allowing us to manufacture narrower glazing bars and thereby closely replicating the existing sashes.


DOUBLE GLAZING SPECIFICATION
Slim 14mm (4/6/4) double glazed units, Planitherm Total+ glass (outer pane) and Krypton gas filled cavity.
Centre Pane U-Value of 1.5 Wm²K
Total Window U-Value of 1.8 Wm²K

New Double Glazed Sash Windows

In addition to replacement double glazed sashes, we also manufacture and install complete new windows with slim double glazed units that comply with Part L of the Building Regulations.
For properties where historic protection applies, single glazed units can also be manufactured with a range of glazing options - ask your Surveyor for details.

TIMBER
The replacement windows are manufactured from either treated softwood or hardwood, the choice will depend upon preference and budget.

GLAZING
As with the replacement sashes, we use slim glazing units, allowing us to manufacture sliding sashes using traditional carpentry methods, including solid glazing bars (instead of ones attached to the glass), to maintain the window’s authentic character and charm. 
The reduced sightline from the slim double glazing units allows us to utilise narrower glazing bars, so we can recreate the majority of historic and traditional sash styles.

DOUBLE GLAZING SPECIFICATION
Slim 16mm (4/8/4) double glazed units, Planitherm Total+ glass (outer pane) and Krypton gas filled cavity.
Centre Pane U-Value of 1.2 Wm²K
Total Window U-Value of 1.5 Wm²K

THE BENEFITS

  1. Reduced energy costs
  2. Up to 30% improvement in energy efficiency
  3. Easy future maintenance
  4. Complies with Part L of the Building Regulations
  5. Perimeter Sealing System tested to BS6375-1 (withstanding 71 mph winds)
  6. 5 Year Guarantee
  7. FENSA certificate provided

INSTALLED AS STANDARD
Our unique Ventrolla system will be installed as standard to your new sashes or new windows.
VENTROLLA SASH REMOVAL SYSTEM (SRS)
To assist with future maintenance and painting, we install our patented Sash Removal System (SRS) that enables both the top and bottom sashes to be removed for redecoration and future maintenance.

VENTROLLA PERIMETER SEALING SYSTEM (VPSS)
All our new sashes and new windows include the unique VPSS draught-proofing system that has been tested to British Standards BS 6375-1 2009 Class 3, withstanding 71 mph winds.
The system is fitted by routering grooves into the mid-rail and bottom-rail of the sashes, or within the inner edges of casement windows, to which a pile carrier is fitted and the appropriate size of weatherfin pile installed.
New parting beads and staff beads are fitted that also incorporate the weatherfin pile, creating a fully draught-proofed window.

THE FINISH
Replacement sashes and new windows are supplied primed, ready for final finishing coat by others.

HARDWARE
All Ventrolla windows are supplied with Brass hardware, other finishes and a range of styles are available. Please ask for a copy of our Hardware Brochure.