Solid Wood v UPVC/Composite exterior door

[Clark Kent]

Sorry if I’m going over old ground, I did do a search but didn’t come up with anything conclusive so….

 

I’m looking to replace the street door, my wife particularly likes the doors by a company called Gileta who do some very nice designs with triple glazed stained glass. I must admit I haven’t seen a composite as attractive without paying a small fortune.

 

The question is, will a solid wood door & frame be much much worse/colder than a composite one (providing it’s all well sealed and draught free)?.

 

I did read a post where someone was suggesting that its such a small percentage of the exterior wall that U value isn’t important as long as it was draught free, if this is the case though then why bother with triple glazed windows?

 

We’re looking to have a door with a window either side to maximise light as the passage is quite dark. I’m planning on making everything in the renovation as efficient as possible whilst working to a budget.

[JohnMo]

So just to add another option into the pile, we have a wooden door, but it's laminated with insulation to give a good U value also.  You have to be careful as some times you get what you pay, sometimes you get ripped off.

 

8 minutes ago, Clark Kent said:

then why bother with triple glazed windows?

Triple glazed come in handy when the are chasing the final percentages of efficiency, if you house is drafty, not well insulated, there are bigger gains to chase other than triple glazing. It's a matter of prioritising the biggest gains first.

[Clark Kent]

7 minutes ago, JohnMo said:

Triple glazed come in handy when the are chasing the final percentages of efficiency

 

I get that, I guess the point I was making is why ignore the U value of a door but not windows.

 

So is the insulation internal? If so I assume it’s custom made. I haven’t actually searched but I didn’t think wood was a terrible insulator, they seem to use it on windows frequently.

[JohnMo]

1 minute ago, Clark Kent said:

is the insulation internal?

Yes, basically a sandwich. In the grand scheme of things it's quite good.

 

If you are replacing anyway, make it the best you can get with cost constraints. Our door has a U value of 1.0, the two side lights are 0.6.

 

When comparing offers look at the whole U value, a lot of companies will just give glazing value.  Frames can leak heat very well and it will just bypass the glazing or the door itself. If a company is unwilling to give the whole U value move to the next company. I had that a lot.

 

You are looking for

U_g is just the glass

U_w is the whole U value

[Conor]

Doors might be a small % overall, but in the spaces they are located, they can be the dominant factor. E.g. in our entrance hall, 90% of the external facing structure is a door + side light. We went for the highest spec door we available in our budget, and it's something like u0.8. In super cold weather, the outside face frosts up and inside the hall is just as warm as the rest of the house.