Learn how poor design of guttering is causing rotting of roof framing.
Poor gutter design causing rot. Learn how to alleviate this serious fault. QBIS.
Roof gutters without eaves are not good building practice.
Some examples of problems resulting from this poor design of roof gutter!
How poor gutter design is causing rot to a roof structure.
- Front edge of the roof gutter is higher than the back edge. This is standard with the majority of roof gutters.
- Small slots were positioned just below the front edge bead were far too small to allow excess water to escape through them.
Another contributing factor to the problem, the down-pipes were insufficient in their size and numbers to cope in severe weather conditions, causing back wash.
Recommended fix to poor gutter design causing rot.
- Fit larger slots to allow excess water to escape to front of the gutters (rather than the back) where it will not cause any serious problems.
- Have additional and larger downpipes fitted.
- If necessary, fit more stormwater pipes.
In normal weather conditions the downpipes will do their job, the enlarged relief slots will serve as a backup and help cope in adverse weather conditions.
Location of problem showing where a poorly designed gutter is overflowing and entering interior of a house.
This photo shows back of the metal fascia where water had been cascading from over back of the gutter and metal fascia also bridging the wall cavity.
In most cases this will not cause problems, but in this particular circumstance flashing incorporated within the wall (above a lower level window) was allowing water to enter a bedroom at a lower level.
Overflowing of roof gutter causing rotting of roof frame.
Here is an example showing consistent overflowing of water from back of the gutter causing rot to the tail end of the roof truss (top chord).
How to maintain your roof also avoid poor gutter design causing rot to a roof frame.
- Always consider the practical advantages of including eaves when having your building designed.
- Do not connect the stormwater to the surface drains, this will overload and cause backwash of water to occur.
- Have large downpipes fitted.
- Ensure the downpipes are connected to large enough stormwater pipes also number of them to carry the water away.
- Check the stormwater system and make sure it is kept clear of debris so it can operate effectively.
- Do not use gutter guards, they allow accumulation of debris to occur below them that will cause premature rusting of the gutters.
Roof’s must be checked and maintained on a regular basis to avoid serious problems from occuring.
For independent Building Inspections Brisbane in all suburbs, Qld Home Buyers Inspection Service. qbis.com.au