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Triple Glazing  

Triple glazing is a great way  to bring the glass you love into the 21st century. When I set your leaded pane into the middle of a double glazed panel and refit it back into your wooden frames, the insulation factor in your home increases immensely and immediately.  The leaded pane is completely refurbished and cleaned and hasn't looked this good since...well, when first built.

Click on any Photo for a big version 


Triple Glazing  

 Leaded windows usually last between 50 to 150 years before the cement, which weatherproofs them, starts to crack and fall out. The window starts to get draughty, rattles, lets water in, which freezes expands and weakens the lead, the joints crack and the window starts falling apart. Even when not exposed to the elements the lead and glass expand and contract at different rates and this causes the cement to crumble and fall out as dust. 

 Internal doors do this through the continual movement from, even, the suction of other doors, but mostly from people pushing the glass and/or being slammed. 

Internal Glazing  

 This internal entrance had exactly these problems.

Around 100 years old the door pane was rattling, the lead joints were cracked and there was practically no cement left in. It had to be repaired and rebuilt. 

The windows in the surround were in great condition but had lost a lot of cement and were draughty.

To Triple Glaze  

 After removing the leaded pane and replacing it with temporary glass. I cut the lead away from the edges then reduced the size of the pane by cutting each piece of the edge glass off. (usually 3-8mm)   I add Y shaped edging lead and solder it on. This is needed to maximize the thickness of  the spacer bars, they are filled with silica gel crystals to soak any moisture trapped in by the hot melt (rubber seal). The upper half of the Y lead shows above the  beads as a traditional leaded edge when refitted.

Click on any Photo for a big version 


Traditional Lead edge  

 When building a leaded panel the first job is setting out the edge lead. this is what holds the panel together and what the glazier putties up to.  After trapping the new lead between the spacers, the window looks as it would have originally, the top half poking out of the woodwork.

When the glass itself is trapped between the spacers it doesn't look as authentic and draws the eye to the worst looking part of the whole process. The aluminium spacer bars.

My Own Personal RANT

UPVC Companies 

  Double glazing companies around the region use me to refurbish and prepare their windows for triple glazing. None of them want to pay to have it done properly. 

For them, I cut the edge lead off and stick some lead tape on. They then trap it between the spacer bars and use the hot melt to hold it in position.

 This cheap unreliable option does not cut the leaded pane to size, use the specialized edging lead or really clean the leaded glass. This option is more likely to lose its integrity and steam up because: 1 the hot melt is thinner; 2  there is less silica in the spacer bar so less moisture removal; 3 the glass is not cushioned from the frame so movement can break the glass; 4  Much harder to take the unit apart as the hot melt has glued itself to the individual pieces of glass (but it is cheaper).


Double Glazing Companies 

 What they really want you to do is replace it with what they say is their new, stained glass, double glazed panel with the same design and same colours. It's NOT !

 I'm sure you'll have noticed  new windows all over the place which just don't look right. The colours are not quite subtle enough to be real or are so garish they offend the eye (usually the glue going off), there's only one reflection, there are lead lines which end in the middle of a blank space (impossible glass cuts) in the pattern.

 These windows were made by a guy/girl in a double glazing company who showed a bit of artistic flair, getting paid minimum wage and copying patterns off the internet or from the leaded glass they're replacing.

 Using sticky backed plastic and lead stuck onto a single sheet of glass these patterns are produced cheaply with bad patterns which usually have, to my eye, impossible cuts in the glass.

 These windows have spread across the country replacing all our beautiful leaded heritage with plastic. SGO (stained glass overlay) can be around £40/m whereas my cheapest leadwork is £50/ft  10 times more expensive. The windows you own are far more valuable than what they replace it with. 

 Whilst I've been posting  leaflets through the doors of houses which still boast their original Stained glass, I've noticed many SGO patterns. The older ones have faded and lost all their colour, the glue which sticks the bevelled glass to the pane has gone off and is now giving a fluorescent green or yellow glow and/or the lead is peeling off. (i do laugh)

 The Oldest coloured glass in this country is in St Peters Church, Sunderland, AD 674. It still holds all the colour that it was produced with,1340 years ago. Real glass doesn't lose it's integrity, it slowly runs away.



  The inside of the leaded glass has probably had around 30 years of central heating caused condensation. Layers of black mould and polish have accumulated and hardened during the summers. This has to be painstakingly cleaned off with a knife, wire wool, polishing brushes and elbow grease. I know this is hard to believe but a 3ft x 2ft leaded window can take up to 4 hours to clean properly.


In these photographs I show the process and work involved in fitting a triple glazed panel into the original woodwork.


  I know you’ll have painted your woodwork every couple of years and really worked to keep them in good condition.

 You will have been tempted to replace them with aluminium or UPVC frames but unlike your neighbours, didn’t want to lose the stained glass by replacing it with sticky backed plastic.

Wood is still THE best insulator. BUT

 If the frames are rotten or you’d just like to replace them because...painted shut, stiff, draughty etc. .The new adjusted panel will fit into any new wooden,  upvc or aluminium frames. I’m a good wood-worker  but sometimes have to use an excellent Joiner who easily  replaces rotten parts.

I first remove the leaded pane. and chop into the bead on the inside of the window.

I then chop it off completely and sand the frame flat

New beads cut to size.

Pine on the inside,

and in this case, teak externally.

The beads are stuck in using nails and Sikaflex (not silicon as this destroys the double glazing sealant).

The triple glazed panel squishes the sikaflex out of the bead and makes a great seal ready to be painted over.

On the inside the beads are sikaflexed in but not to the glass. if removal is ever necessary it can be easily done from the inside.

This example invoice is real, and all times were recorded to see if i was losing or gaining by my estimations.

 I first remove the old putty and very carefully separate the leaded window from the painted inside woodwork.

I then cut a square (corners), temporary replacement piece of glass and putty it in, remembering to record the exact size the triple glazed panel will have to be.

Chop off the outside lead , cut glass, fit Y profile lead.

CLEAN  (I hate cleaning)

I have to cut and scrape the area immediately next to the lead, brush (brass brush) , wire wool every bit of each piece, then cloth then boot brush to polish. It can be monotonous and take ages depending on how bad the black mould has been over the years.

Take it to the double glazers. sometimes it's done in 2 days but sometimes, if they're very busy 2 weeks.

Remove temporary glass, chop of mouldings, sand flat, chop new beads (handmade by me), fit triple glazed panel, seal, clean.


  When i'm working on your windows i'm generally doing more than one in a day and there is a lot of time that can be saved.  i usually estimate and charge  £250. each when there are more than two. 

Doors can be trickier especially because of the thickness of the door and the special beads i have to make to accommodate the thick panel. It may also need strengthened and usually needs the joints resolderred. I really have to see it to estimate the cost but usually not more than £500.

Leaded Lights

  These panels are situated as toplights in a bay window in Newcastle. They were badly bowed and were cracked in many places. the lady, who had just moved into the house, had inherited 3 similar panels saved from elsewhere in the street.

  I removed them, repaired them, matching perfectly using the glass recovered from the other panels, then encased them in a double glazed panel thus making it a triple glazed panel.

   I then recessed the woodwork to accommodate the larger thicker panel and refitted them into the bay. I also changed her single glazed windows and door with double glazing. 

   She Now has a very much warmer living room.

Stair Windows 

  These windows are on the landing half way up the staircase, this one opposite is  a very beautiful picture and actually huge measuring 6ft high. It is the Mankiest window i have ever had to work on and the client got a bargain because of my underestimation. It took me almost 25 hours to clean, the black mould was 5mm thick in some places.

  The window with the coats of arms was the first time i had to remove the rusty opening metal frame from the centre 2, this is  why i rebuilt them with the blue border on, it takes up the space that the metal frame took up.

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Sash Windows 

  These windows are a bit different to the usual ones that i do. The top coloured patterned section is done in exactly the same way as explained above and the smaller, clear sections were also done in the same way by a joiner who i taught. 

 The small sections were vey difficult and time consuming and also made the panels seem much smaller but as you can see they look very acceptable and also passed the conservation area guys visual test.

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