Secondary glazing/Reglaze...?

Hi All,
I've recently bought a house which is approx 25 years old and has large floor-ceiling wooden windows. The windows only have 1 moving pane per window for ventilation. Unfortunately they are pretty poor windows in the winter for keeping the heat inside , as we'd much rather keep the windows i'm wondering what's the best method to making them more thermally efficient. Is it worth replacing the glass with thicker thermal glass and resealing or leaving them alone and adding a secondary glazing barrier?
I'm no whizz with windows woodwork and they don't seem easy to get the glass out so its likely i'm going to have to get a glazer in but is there a secondary glazing option on the market or will it be a custom install?
Any ideas/suggestions are appreciated.Cheers.
Jim

I came across the website below when I was considering a similar situation.
http://www.magnetite.com.au

No idea if they're any good but worthwhile exploring cost & effectiveness if you go this route. Let the forum know how you go if you do.

I haven't done anything to mine yet, although I'm thinking of doing an unorthodox solution ie. leave the window frame, architraves in place, then use the Arbotech Allsaw to remove the parts of the window within the frame. Then I order double glazed windows to fit into the old frame. This will mean my glass surface area is reduced, but that is fine for my situation.

If anyone thinks this won't work for any other reason, would appreciate your comments & reasons.

Cheers.

I've done one of my windows with flyscreen aluminium frames silconed to inner frame. Then buying clear plastic(gazebo stuff?) off the roll at Bunnies(not the thinest stuff the next one up) and installing it as you would the flyscreen mesh. This gives a taught finish. The net curtains were then re-installed(further out than before), and you can't see the difference. I'm getting round to doing the lounge before winter There are limitations with the size of the alloy strips and the width of the plastic available.

cheers

gravy

I had a chat with the Magnetite guys, and it appears - not having actually used them - that they are good but $exxy, e.g about $600 for a 2 x 2 m window. Marginally cheaper per unit for more windows.

What Magnetite do is fit a thermally-efficient second glass panel to the outside of the window. All have to be custom made to suit your window dimensions, of course.

This can be removed for cleaning, change of seasons etc.