Expert: Randy Brooks - 3/21/2010

Question
Hello,

I live in Vancouver, BC, Canada, a region on the west coast that receives  significant amount of rainfall in the fall/winter months. Our chimney is constructed with cinder blocks and the flues have no covers/caps to prevent rain from entering the chimney. We have lived in the house for 7 years and have never used either fireplace (1 up/1 down).

Approx 3 years ago, the lower fireplace saturated with water and bled out onto the floor, creating a small flood situation. We had a sweep service recommend caps, however, wanted to charge a huge amount to perform the service. As a result, I just placed a paving stones over the flues to prevent the rain from entering the chimney. We also recently suffered another issue in which water was running our roof and saturated the exterior of the chimney. Unfortunately, that moisture seeped inside, and created some mould and damage. We have since had the water re-directed, the exterior cracks filled and had it sealed with a clear spray on membrane. It appears we now have the exterior issue re-solved, but are still concerned about the moisture in the flue. We are planning to install an electric insert in the the lower fireplace opening and having it framed in as the basement has to be restored due to the aforementioned mould/damage.

Now that I have hopefully given you the background, here are my questions.

1) Should I be covering the flues with the paving stones or should I have caps installed to prevent rain from entering the flues?

2) will caps provide sufficient protections from rain entering the flue?

3) do the flues require ventilation or is ok to seal them off??

4) will there be any safety/electrical issues with having an electric insert installed with the possibility of some rain entering the flue?

Any thoughts/opinions/idea would be greatly at appreciated.

Trev

Answer
Trev,

1) Should I be covering the flues with the paving stones or should I have caps installed to prevent rain from entering the flues?

Caps.

2) will caps provide sufficient protections from rain entering the flue?

Yes.

3) do the flues require ventilation or is ok to seal them off??

Ventilate.

4) will there be any safety/electrical issues with having an electric insert installed with the possibility of some rain entering the flue?

Yes.

Any thoughts/opinions/idea would be greatly at appreciated.

I would have an extensive inspection performed prior to doing anything. Hope this helps.