Glossary of Terms

To help you understand the terms we use to describe our products we have put together a glossary of terms, please see below:


What is a lintel?

A lintel is a reinforced beam that is used above doors and windows to support the above brickwork so that it isn’t being supported directly onto a window or door.

Other names: Concrete Lintel, Stone Lintel, Catnic Lintel, Steel Plate Lintel.


Low E glass

What is low E glass?

Insulated coated glass that helps reduce energy loss.

Other names: High level U value Glass, Planitherm Glass, Diamante Glass.

Mortice Lock

What is a Mortice Lock?

High security lock used on doors.

Other names: 3 Hook lock, 7 point lock, Locking system.



What is a Mullion?

Are vertical bars on windows or doors, to divide whole sections up.

Other names: False mullion, dummy mullion.


Multipoint Locking System

What do you mean by “multipoint locking system”?

Both the door and the frame are locked together at multiple points.

Also Called: High security locks, 8 point locking, Shoot bolt, ESPAG locking.


Night Vent

What do you mean by “Night vent”?

Ventilation grills that allow air flow on windows and doors.

Other names: Trickle Vents, Ventilation Grills, Air Flow Vents, Grills.


One Way Screw

What do you mean by One way screw?

Self tapping screws that only go in one way.

Also Called: Self tapping screw.



What is a Pane?

A glass unit.

Also Called: Panel of glass, Unit, Glass panel, Half panel.


Patio Door

What is a patio door?

A sliding glass panel door (going out to a patio garden).

Other names: Sliding Door, 2 Pane Patio, 3 Pane Patio, Internal Sliding Door.


Plant on Bay

What is a Plant on Bay?

Bay window that is from floor to ceiling. Can walk into.

Also Called: Walk in Bay, Walk in Bow, Flat Roof Bay, Tiled Roof Bay.



What is a profile?

Lengths of plastic that makes the window or door frames.

Other names: Extrusion, Lengths, PVCU lengths.



What does PVCU stand for?

PolyVinyl Chloride Un-Plasticised.

Also Called: UPVC, Plastic Windows.



What does Reinforcement mean in windows?

Helps strengthen windows & doors.

Other names: Steel Reinforcement, Aluminium Reinforcement, Box Section, Hollow Section, T-Section.



 What do you mean by?

To cover over the house brickwork.

Also Called: Pebble Dash, Fine Rough or Smooth Render.


Residential Door

What is a residential door?

The main entrance door to a property.

Other names: Front door, Main door, Entrance door, Outer door.



What is a Reveal?

The wall directly to the side of a window or door on the inside of  the window frame.

Other names: Window Ledge, Window Sill, Window Frame, Door Way, Window Cheeks.


Restrictor Device

What is a Restrictor device?

A way that a window can be stopped from fully opening to help with safety.

Also Called: Child Restrictor Locks, Fire Escape, Easy Clean.



What is sash?

A window that has overlapping sliding windows.Normally 2 panes of glass that slide up and down inside a frame.

Also called: Vertical Sliders, Top Light, Fan Light.



What is Sealant?

Materials used to seal the window or door to the wall cavity.

Other names: Rubber Seal, Silicone, Stelmax, Putty.


Secondary Double Glazing

What is secondary double glazing?

An internal glass frame that fits inside your original windows.

Other names: Internal Glazing, Glazing Kits.



What is a Shootbolt?

A form of high security locking system used in windows.

Other names: Finger Bolts, Hook Locks.


Side Lights

What does side lights mean?

A panel to the side of a door, Usually fully or part glazed.

Other names: Side panels, Glass panels.


Sill / Cill

What is a sill/cill?

External window ledge.

Also Called: Cill, 150mm cill, 180mm cill, Window Ledge, External Cill.



What is Snib?

The way to latch a lock on a door.

Other names: On the latch.



What is a Soffit?

The underside of an exterior overhanging roof eave.

Also Called: Eaves board, Hollow board, Roof eaves boarding, Fascias.



What is a spindle?

Internal mechanism of a handle.

Also Called: Split Spindle, Thumb lock.



What do you mean by Surveying?

An accurately detailed inspection and measurement report of the site.

Also Called: Measuring up, Site survey, Site measure.


Tempered Glass

What is tempered glass?

Toughened safety glass designed to shatter with no sharp edges.

Also Called: Shatterproof glass, Safety glass, Treated glass.


Thermal Break

What do you mean by thermal break?

The gases used in insulated glass panes is used as a thermal break to prevent the thermal energy being dispersed between the glass.

Other names: Spacer bars, Reinforced thermal bars, Thermal bars.



What is a thumbturn?

A locking devise used in doors and windows.

Other names: Spindle lock, Lock and Key devise.



What is a Transom?

Horizontal bar that divides a window or door.

Also Called: False transom, Dummy transom.

Tilt and Turn Windows

What is a Tilt and Turn Window?

An inwards opening tilted window.

Other names: Swivel window, Tilt windows, Inwards opening windows, Push out window.


Toeing and Heeling

What does toeing and heeling mean?

A fitters procedure used to correctly hang and fit a door.

Also Called: Packing glass, Fitting packers.


Toughened Glass

What is Toughened glass?

Glass that has been treated and put under heat and coolant processes.

Other names: Safety glass, 6mm glass, Pilkington glass.


Vertical Sliding Window

What is a vertical sliding window?

A window that has overlapping sliding windows. Normally 2 panes of glass that slide up and down inside a frame.

Other names: Sash windows, Tilt and Turn, Top light, Fan Light.


Window boards

What are window boards?

Internal window sills.

Also Called: Duraboard, Softwood boards, Window cills, Window ledges.


Wood Grain Finish

What is wood grain finish?

A foil wrapped treatment that allows a grain appearance and colours to PVCu or aluminium finished windows and doors.

Other names: Oak windows and doors, Mahogany windows and doors, Wood grain windows, Wood effect windows, Rosewood windows, Stain grain windows.

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