Wires through external wall, needs sealing?

[skyhawker]

If wires are prepared from under the floorboards to outside an external wall eg for future air con do the holes need to be sealed with render or something similar in the interim or is it safe to leave?

 

[PrenticeBoyofDerry]

They should be sealed to prevent water tracking back in to the property, I normally seal around cables with silicon and also have a drip loop on exposed cables.

 

[theprinceofdarkness]

Always route the cable on the outside UPWARDS. So even if the cable is coming down the wall, put a loop under the hole and bring the wire upwards into the hole. Seal the hole with silicone goo. Cables that rundown an outside wall have water running down them when its rains, the loop is so this excess water drips of down the wall and not straight into your hole.
Frank