There are increasing problems with condensation in the roofspaces of newly built homes in Victoria. This problem has increased each year however this year is by far the worst.
This is of course mostly due to the new mandated energy ratings that lock up the roofspace with the over use of insulation without effective ventilation, also due to the new BAL ratings for all Victorian areas, these BAL ratings of course are necessary.
Then there is the major culprit bad building practice.
SO WHAT IS THE SOLUTION TO THESE NEW ISSUES AND BAD BUILDING PRACTICE
Well, for the issues of energy rating over kill and the BAL ratings – very effective roofspace ventilation will remedy the condensation problems caused by these mandated requirements. When it comes to effective roofspace ventilation there is no comparison to the effectiveness of Universal Tile Ventilator Systems for tiled and colourbond roofs.
WHAT IS THE MOST COMMON BAD BUILDING PRACTICE THAT CAUSES CONDENSATION PROBLEMS IN THE ROOFSPACE
First problem would be to not have any vapour barrier at all (no sarking of any descrition). Under a corrugated metal roof this is the equivalent of playing Russian roulette with a full magazine.
The second and most common is – the roofer fixes the sarking tightly across the rafters, bringing the sarking into or almost into contact with the roof sheeting by doing this renders the sarking useless. This will increase the problem of condensation.
The third bad building practice is to use any type of vapour barrier at all for example insulation foil (sarking) or blanket with foil without effective roofspace ventilation.
THERE IS YET ANOTHER PROBLEM THAT HAS INCREASED ROOFSPACE CONDENSATION AND THAT IS THE USE OF METAL BATTENS
The use of metal battens under metal roofing has further increased and exacerbated condensation problems with metal roofing. These metal battens have introduced condensation problems that did not exist when timber battens for metal roofing were in use. Metal battens work like a wick to run condensation throughout the roofspace.
SO WHAT IS A SOLUTION FOR THE BUILDER IN VICTORIA TO WALK AWAY FROM A BUILD KNOWING THEY WILL NOT HAVE PROBLEMS WITH ROOFSPACE CONDENSATION
If you must use sarking:- number one use only timber battens – second make sure that the roofer slumps the sarking 50mil between the rafters so the sarking has no contact with the metal roofing. Thirdly and most importantly install effective roof ventilation to the roofspace. Walk away with confidence.
HOWEVER IF I WERE TO CARY OUT THIS WORK WHAT SOLUTION WOULD I RECOMMEND FOR THE ABSOLUTE BEST RESULT
- Get rid of those metal battens, they are causing more problems than you would believe possible. Do what you used to do when you stand your trusses or pitch your roof - batten it out with timber battens.
- Preferably use blanket foil insulation 50 or 75mil under the roof sheeting.
- Then you have to have very effective roofspace ventilation to allow the heated moist air underneath to escape the roofspace and not build up. When we say effective ventilation we do not mean whirlybirds these simply do not work – check out on this site – Case Studies & Reports “Whirlybirds Don’t Work”. You need a roof ventilation system that has inlets and outlets in the roof covering to allow the ambient air to circulate the roofspace and get rid of the built up heated moist air – result no condensation problems our Smoothline Ventilator Systems (for corrugated roofing) have solved many condensation problems caused by bad building practice and some just won't go away.
This problem just simply does not go away it will be back to haunt you next winter, so do it right in the first place.
To the homeowner make sure your builder does the right job so you don’t end up holding the turkey.
So when you want effective roofspace ventilation for a corrugated colourbond roof you can’t go past the Smoothline Ventilator System from Universal Tile Ventilators.
Walk away with the utmost confidence.
PREPARE TO BE AMAZED
ANYTHING ELSE IS A COMPROMISE