All about installing wall and chimney brackets.

Also see :
- Brackets and clamps
- Brackets/Galvanising tests
- Our pole and bracket lifetime warranty

Brackets are classified according to their size (from the top pole clamp to the bottom one) and their "stand-off", that is to say the distance from the wall (or chimney) to the pole will be when it is "in-situ". The latter may be significant if the pole has to clear an overhang above it but bear in mind that these dimensions are to the end of the bracket, 3" to 4” will be "lost" in accounting for the width of the pole / clamps, see picture below. When working out the required stand off (or pole offset) you need to clear an overhang we strongly advise against estimating this ! Unless you are sure, get up there and measure it exactly because you’ll kick yourself if you end up with a bracket (and/or pole) with insufficient stand off......
Next add about 2” to this figure, it can be more, but that is just "wasted" stand off. This is to prevent high winds causing the pole to bang against the fascia (or gutter) and also to facilitate maintenance of the latter.

But always remember you don’t have to use a huge “stand off” bracket if you can use a cranked pole !

When installing a wall bracket always leave 2 to 4 courses of bricks above the install *, and try to make it 4 to 6 courses if installing the aerial at the top of a gable.

* Depending on the size of the aerial and the length of the pole, and whether you’re using a Black and Decker or an SDS hammer drill to drill the holes......

There are basically three main variants of the type of bracket used on many smaller installation jobs, that is to say the 6"x6" bracket (wall or chimney mount).

The cheapest type of the three is the pressed steel bracket. It is galvanised but it is of the “Pre-Galv” type. Although this is far preferable to just being painted, it will not remain rust free anywhere near as long as a "hot dip galvanised" bracket would. As the name implies it is just a bent piece of metal sheet (typical thickness 2.5mm) and it is not in the same class (strength wise) as a welded bracket (in fact they're so weak they can even be bent in imaginative ways) and most only take three wall anchors.
The next category up is the welded (but painted.....) bracket. These are significantly stronger than the pressed variety and are welded together out of steel angle/bar of typical thickness 3.0 to 5.5mm. Welded brackets are available in either painted or galvanised finish. Although there is no difference strength wise between them the difference in finish is chalk and cheese. A painted bracket can start rusting almost straight away and will often show significant surface rust within a few years. It must be admitted that it’d usually take decades for rust to significantly weaken a painted welded bracket, but it will do so eventually ! Thus, at the top of the tree, is the welded hot dip galvanised bracket, even damaged galvanising still doesn't rust. It will come as no surprise to learn we only stock those……

The picture shows a 6”x 6”, a 6”x 9”, and a heavy duty (angle section steel) 9”x 9” wall bracket. We also sell heavy duty wall brackets in 12x12 & 12x18.
All our brackets are of welded construction and “Hot Dipped” galvanised (to BS EN ISO 1461).

Note ! Remember to order the V Bolts (plated or stainless) with the brackets !
We also sell the wall anchors for our brackets.

The picture illustrates the difference in construction standard between a pressed Chimney bracket and a welded type. Perhaps even more striking is the amount of rust on the “Pre-Galv” pressed bracket.
Note the “failed” steel pole, it departed this world due to rust.

Here we have a pair of the smallest generally available T&Ks the 12", plus a pic of the largest, the 36". Note the additional diagonal bracing on the latter.

It must be stressed that T & Ks are used to gain more stand off (also see 12x12 & 12x18 heavy duty wall brackets), not because they’re stronger than a pair of smaller brackets, particularly if the latter are of the welded variety. So long as the pole’s V bolts will fit the bracket there is no reason why even two standard wall brackets (or low profile brackets) cannot be used for a long pole and/or large aerial. Quite apart from anything else a pair of smaller brackets will have eight wall anchors and four V bolts to secure the pole, as against only five anchors (though more can be fitted, see below) and two V bolts for a standard pair of T&Ks. Remember : more wall anchors = a stronger install (the wall anchors usually fail before the bracket) and this is particularly important when the forces are towards/away from the wall. Alternatively use sleeve anchors.

“T”s and “K”s are available separately (here) and two “K”s are obviously a bit stronger than a T&K, though it must be admitted there are relatively few installations where this would be of consequence, after all, the pole would generally fail before the bracket anyway ! However, each “K” does take three wall anchors (in fact the “K”s we sell have a fourth hole just at the point the two base plates are welded together) whereas each “T” only takes two. This can be significant if there are loads of voids in the brickwork and some of the wall anchors won’t tighten…… Alternatively, if using a “T” with a long pole and/or large aerial, consideration should be given to drilling additional holes (they won’t rust if the bracket is hot dip galvanised) in the bracket’s baseplate to allow the use of additional anchors.

There are two opposing views as to which bracket (the T or the K) should go at the top. The K is obviously the more robust bracket and the received wisdom is that this should go at the bottom because, being further down, the wall is stronger there. However the top bracket is probably under the most stress (certainly if the wind is blowing the pole away from the wall) and so some think the K should go there instead !  Basically one has to work out the relative importance of the two factors for the particular install being undertaken. For an install at the peak of a gable I would put the K at the bottom, whereas on a strong flat top wall I’d put the K at the top. Basically it’s six of one, and half a dozen of the other, but, if in doubt, put the K at the bottom !

Note that low profile brackets don’t allow any adjustment of the poles stand off so should only be used on a flat surface.
Available in Pre galv with plated bolts or hot dip galv with stainless bolts.
Low profile brackets look very neat and if standoff is required this can be achieved by using a cranked pole.

Coffee & Cream
Do you really want that on the front of your house ? ! ?

It isn’t uncommon to see rusting steel brackets fitted on the apex of rendered walls with huge rust stains stretching out beneath them.... All for the sake of a bit of decent galvanising. The latter is just what you get on a galvanised welded bracket and these are the only type we sell. None of your thin finish "Pre-Galv" here, this is "Hot Dipped" galvanising (ours are to BS EN ISO 1461) and it is very impressive. We’ve seen brackets that have been up 25 years plus without a trace of rust staining. In fact we’ve got some experiments running where we’ve actually tried to file off the galvanising finish (on a section of the brackets) and left them outside in the rain
Despite having damaged galvanising they haven’t rusted at all in over 15 years, that's FIFTEEN YEARS !
I really wonder how anyone, no matter how big a bodger they are, could possibly contemplate using a painted bracket. They must be tighter than a camel’s arse in a sandstorm.......

It must be admitted that in most locations and/or for most jobs galvanising is primarily about appearance, it would take years and years for rust to significantly affect the strength of the bracket, though a somewhat shorter time if you live by the sea ! BUT, as the adjacent picture on the shows, hot dip galvanising's superior rust prevention can also be about the long term strength of the install……

Not all galvanising is created equal....

These saddles have been in salt water for 2 years, the top one is hot dip galvanised, the bottom one is Pregalvanised.

Also see galvanising tests.

The tilting bracket (sold here) is specialised for, well, tilting. This product is very handy when you need to point your pole anything other than parallel with the wall (or whatever). This bracket is not intended for heavy duty applications (indeed it will only accept a 1 inch pole), but having said that it’s actually rather stronger than it looks !
The bracket will allow +/- 50deg (approx) of tilt from the perpendicular.
Note that there is an alternative to this bracket, an L Section loft kit, but insert the short of the L section into the side of the supplied two way bracket (see picture on the link). You can now rotate the pole to any angle +/-90 degrees.

The simple answer is that it’s bad practice and it shouldn’t be done unless there is absolutely no alternative. A bracket mounted on a wall (with the appropriate pole to clear any overhang) is far stronger than just attaching it to a fascia or bargeboard. Furthermore screwing brackets to wooden boarding greatly increases the chances of rot setting in and makes it more awkward to repaint them as well. Finally, many people will eventually have UPVC replacement fascias fitted, and then the bracket will need moving anyway.
I don’t even want to think about anyone actually screwing an aerial to a UPVC fascia.........

When it’s called a wall bracket, that’s for a reason. They’re not meant for chimneys. That would be a, what do they call it ?   Ahh yes, a chimney bracket.......    (pictures courtesy of Vision)

Some installers fit “Self Supporting Brackets” (sometimes called “Bang Bangs”) which do not utilise a lashing wire. They have two “L“ shaped pieces of metal which are hammered into the mortar between the bricks, hence the term “Bang Bangs”. Unless access problems are severe (and two are utilised to increase the support) most riggers know they’re a bodge because the strength of the install depends on the mortar around just two bricks at the corner of the stack.

Bertie Bodger's “Bang Bang” Bracket
Note how the masonry has been pulled out, and that’s out of a wall, not a (weaker) chimney stack......

For aerial poles up to 3ft supporting small or medium size antennas we recommend and stock the 6”x 6” bracket. It is important to stress that a 6” welded bracket won’t “fail”, it’s the masonry which will go first, because a 6” bracket only spreads the load across the corners of two bricks, see adjacent picture [link] For other installations using poles up to 8ft and aerials up to the size of an XB10 we sell the 8” mitre bracket. If an XB16 is fitted with an 8” mitre we’d go up to a 6ft pole.  An 8” mitre usually covers three bricks and to a greater “depth”, see picture below left. The mitre bracket should also be used if your brickwork is in poor condition.
Unless the aerial is small poles of over 8ft usually require a pair of brackets.
See bracket to pole recommendations

An 8 inch mitre chimney bracket in use. Note that the load imposed by the installation are spread over three courses of bricks and to a greater depth than simpler types of chimney bracket, compare to 6” bracket install above. Note the pre-terminated lash wire (see below).
Pair of Heavy Duty Chimney Brackets. These are exceptionally strong but must be used as a pair with two lashing wires.

Here we have a 6”x 6” and 8”x 8”(mitre) chimney bracket, and the contents of a “Lashing Kit”. The latter includes 5m of pre-terminated wire, 2 x 1.5” V bolts and 6 plated washers (4 x M8 + 2 x M10).

If your chimney is bigger than 5m we stock a 10m length of the 7 strand galvanised lashing wire. This can be either used instead of the supplied length or used to extend it . Note that using long lash wires (or extra joins) increases the chances it won’t tighten up, so pull it as tight as possible (round the chimney) whilst making up the lash. Incidentally, do not confuse lash wire with thinner catenary wire, 7 strand lash wire is approx 3.7mm in diameter and weighs about 65g per metre.

Close Up of lash wire terminations
Above is a “pre-terminated” end, our stock lash kits come with one end like this. The one below is made up by the installer, with the lash wire at the correct length to fit round the chimney and hold the bracket tightly on the side of the stack.

See Installing a chimney lash kit.