Chimneys and parapets
What does rust staining from a television aerial bracket tell you if you cannot see a crack in the stack?
It tells you the bracket or its bolts are corroding, not that a crack has been proved. Orange staining in the mortar is different from an aerial that has already split the stack, and a stain may be the start of bursting joints or surface rust only. A home survey should not call it a crack unless a crack was seen, and it does not test the aerial or the cable.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
Metal fixings in mortar rust, expand and can eventually crack the joint. That sequence is why the stain matters, and why it is not yet the crack. The honest sentence is “rust staining from the bracket, no crack seen”, or “crack seen at the bolts”, depending on the wall. A photograph that only shows a brown streak does not upgrade itself. From the ground the back of the stack, where many brackets are, may be hidden.
Taking an aerial off, or replacing bolts, is a small job only if the masonry is still sound. There is no standard price, and a home survey will not climb the stack to torque a bracket. If you do not need the aerial, ask whether it should come off before the bolts get worse, and ask a mason if the joint is already open. Do not repoint the whole stack because one bracket has wept rust. Do not ignore staining that lines up with a damp patch inside at the same height.
What should you ask your surveyor?
- Did you see rust only, or rust and a crack?
- Which face of the stack carries the bracket?
- Is there a damp patch inside at that level?
What are the typical next steps?
- Describe the stain accurately if you ask a mason to look.
- Do not call it a cracked stack without a crack.
- If the aerial is redundant, ask about removing the bracket rather than painting the rust.
Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.
Also asked about this
Is a satellite dish the same?
It is another metal fixing. The survey should say what is fixed to this stack. Rust from a dish is still rust, not automatically a crack.
Does a sky dish cable through a flashing get included?
A cable through a flashing is a roof detail. Keep it separate from rust in the mortar.