Home > Companies > Ventrolla Sash Window Restoration > Double Glazed Replacement Sashes

Purpose made double glazed sashes for replacing original single glazed sashes, giving a double glazed solution without major disruption to the property. Fitted into existing sash box frame.


  • Reduced energy costs.
  • Easy future maintenance.
  • Minimum disruption and redecoration to the property.
  • Perimeter sealing system tested to BS 6375-1 (withstands 71 mph winds).
  • Five year guarantee.

Standard product features


The replacement sashes are manufactured from hardwood.


Supplied sprayed with a high build base coat Teknos 3130 and an anti-stain primer Teknos Antique White, ready for final finishing coat by others.


Slim Saint Gobain Planitherm Total+ Glass (outer pane) with dual seal edge technology. The units comply with BS EN 1279 parts 1-6 (however, installing replacement Double Glazed sashes into an existing box/ frame is outside of Building Control).


The sashes are manufactured using traditional carpentry methods, including ‘through solid’ glazing bars, which help to retain the windows authentic feel and look. Another main feature of the slim glazing unit is the reduced sightline of the spacer bar between the two panes of glass.

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):

Includes unique VPSS draught proofing system which has been tested to BS 6375-1, Class 3, and withstand 71 mph winds. The system is fitted by routing 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.

Thermal performance (U-value):

- 14 mm units:

  • Centre pane: 1.5 Wm²K.
  • Total window: 1.8 Wm²K.

- 16 mm units:

  • Centre pane: 1.2 Wm²K.
  • Total window: 1.5 Wm²K.



Supplied with hardware, optional finishes and a range of styles are available.

NBS Specification

NBS Create logo
This product is associated with the following NBS Create clause:
45-25-99/350 Wood window units

NBS Specification

NBS Buliding logo
This product is associated with the following NBS clauses:

Product specification

An important note about specifying



Ventrolla Sash Window Restoration


+44 (0)1423 859323

Product reference

Double Glazed Replacement Sashes


[As drawing]
[As schedule]


 - Type:
[14 mm double glazed units]
4/6/4 units with Argon gas filled cavity.
[16 mm double glazed units]
4/8/4 units with Argon gas filled cavity.
 - Spacer:
 - Glazing bar:
[ ______ ]

Ventrolla Perimeter Sealing System (VPSS) location



[ ______ ]

Manufacturer details

Ventrolla House,
Crimple Court,
Hornbeam Business Park,
North Yorkshire, HG2 8PB
Tel +44 (0)1423 859323
Fax +44 (0)1423 859321
NBS Plus