Warm Deck Dormer Roof - Is this correct?

andyuk2005

I don't think anyone watched this video we all seem to be talking about??!! He was very detailed in comparison and appeared very unbiased, and it didn't seem like a sales video at all! And I'm referring to standard dormer flat roofs, which generally, where no exceptional circumstances stand in the way, are now mostly built as warm decks. I can't find anyone else who has said otherwise, which is about a dozen people, on top of the literature and videos all over the net! Please please please just give is a google and see what pops up!! I'm not making this up!
And if a very good builder can build an efficient cold deck with no bridging, why would they?! As explained, considering no special circumstances, it is cheaper, easier and quicker to do a warm!!

Plus, the idea that more space because of a warm deck means more area to heat doesn't entirely work when thought through. The whole idea is that warm decks are GENERALLY more efficient in keeping heat in. That's the idea of insulation, not letting heat escape. Which would you rather; a smaller roof space that loses heat, or a bigger roof space that doesn't let heat escape?

Now, will cyclone give me my engineering degree??!

System

andyuk2005 wrote: »

Plus, the idea that more space because of a warm deck means more area to heat doesn't entirely work when thought through. The whole idea is that warm decks are GENERALLY more efficient in keeping heat in. That's the idea of insulation, not letting heat escape. Which would you rather; a smaller roof space that loses heat, or a bigger roof space that doesn't let heat escape?

Now, will cyclone give me my engineering degree??!

Have you watched the videos?! The salesman on your own video has down as a disadvantage of the warm roof is that you can't always get as much insulation in this situation because it adds depth to the roof (which in retrofit applications can be difficult)
You can design each type of roof to be incredibly efficient with todays materials, however, you seem to be picking retrofit application on dormer roofs as the only instance where you have a choice between cold or warm roof decks - and also where there is a history of badly built cold roof decks...

I'm not sure how this thread went from you asking if the construction of your new roof was correct to you becoming an expert on the only way to do flat roofs :rotfl:

cyclonebri1

the_r_sole wrote: »

Have you watched the videos?! The salesman on your own video has down as a disadvantage of the warm roof is that you can't always get as much insulation in this situation because it adds depth to the roof (which in retrofit applications can be difficult)
You can design each type of roof to be incredibly efficient with todays materials, however, you seem to be picking retrofit application on dormer roofs as the only instance where you have a choice between cold or warm roof decks - and also where there is a history of badly built cold roof decks...

I'm not sure how this thread went from you asking if the construction of your new roof was correct to you becoming an expert on the only way to do flat roofs :rotfl:

:T:T:T:T:T Hence the spammer comments of mine, which to be honest are gaining strength

andyuk2005

I concur with you entirely how it is absurd that this thread went from kindly asking for advice on 1 roof to it being a comparison between two different techniques!! It's ridiculous and should be taken elsewhere!

As for the 'salesman', I remember it has his phone number on there, try giving him a call and have a nice long chat about the pros and cons and I'm sure it will be all cleared up! As for now, I think it is safe to say that GENERALLY, on FLAT roofs where there is sufficient space available, warm decks are MORE OFTEN THAN NOT, the cheaper, easier and quicker option.

Cyclone, on a completely different subject, my cousin is a bank manager in Nigeria and is having trouble moving money out of the country. I am happy to put you in contact with him and he will be happy to pay you a commission to the sum of $12,500,000 dollars. Please provide your bank account details.......!! You spamhead!

System

I guess I just don't understand how someone that can't understand the way a warm roof has been constructed (~10 days ago) is now in a position to be offering advice on how they are better and cheaper than other options - you should get some PI insurance if you are going to be advising people on their construction (you will need it!)

andyuk2005

Well I suppose you are in the same position! Maybe you have that 'PI Insurance', except you must stand out in your industry for being one of the only ones left with your view point?! All I have done is collated the majority of industry facts and opinions on this subject. So far the only people who don't agree with them can be found on this one thread!

Do you not agree with the sentence 'GENERALLY, on FLAT roofs where there is sufficient space available, warm decks are MORE OFTEN THAN NOT, the cheaper, easier and quicker option.'

I certainly don't mean to tease and annoy, that was not what I set out to do or intend to do in any of my responses, unless I receive it first
But I do feel obliged (especially as the thread creator) to ensure that information on here is generally correct, as I have been in a position where I lost out on £60 because I read outdated and incorrect advice on another forum (for something completely unrelated of course!) So forgive me then, for my persistence!

System

do you not agree that each build up has advantages and disadvantages and that each type of roof can be successful/cheap/easy etc in the right situation with the right detailing?
Do you not agree that the detailing and specification of each type is a main driver in the cost rather than just what type of roof it is?
I wouldn't advise anyone unless I knew the specific application required and what the requirements were - and I certainly wouldn't make any sweeping generalisations about either.
Each type of roof has applications where they are more appropriate

cyclonebri1

andyuk2005 wrote: »

Cyclone, on a completely different subject, my cousin is a bank manager in Nigeria and is having trouble moving money out of the country. I am happy to put you in contact with him and he will be happy to pay you a commission to the sum of $12,500,000 dollars. Please provide your bank account details.......!! You spamhead!

ZZZzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz

And now HE calls me a spammer, :rotfl::rotfl::rotfl::rotfl::rotfl::rotfl::rotfl:


Last question, what was it you wanted to know???

andyuk2005

I agree that cold decks can be advantageous in certain circumstances, but as I said generally warm decks are better. I'm only repeating what the industry is saying. Take one of the leading bodies NPS who are part of the royal institute of british architects;

'This ‘cold deck’ construction is considered problematic in the humid, temperate climate of the UK where the effective ventilation of restricted roof voids may be impractical, particularly in sheltered, built-up areas. It is universally recommended that cold deck flat roof construction should be avoided.'

http://www.thenbs.com/topics/ConstructionProducts/articles/ventedUnventedRoofConstruction.asp

I take it cyclone has lost all serious interest in this debate now!!! I don't quite think you got my humour earlier!

System

but again, you are quoting bits of specific guidance and applying them to general situations - you have clearly bought into a single solution to complex problems because it's what you have found on the internet and had installed yourself - now you are the expert on flat roofs (even tho 10 days ago you weren't sure if your own was built properly)