Chockstone Forum

      Sponsored By
      ROCK
   HARDWARE

Chockstone Photography

Australian Landscape Prints

Chockstone Forum - General Discussion

General Climbing Discussion

Author

Anchoring a top rope at home


Dizzy

30-Mar-2009
7:47:25 PM

Hi,

I'm in the early stages of planning a 3.6m high climbing wall for home (one side of my courtyard has a
9m high wall as the boundary - not good for letting the sun in but very good for putting a woodie
against it). One of the ideas I'm tossing around is putting in an anchor for a top rope so my daughter
(aged 3.5) can do some climbing. She loves climbing on the woodies and climbing walls she's been
exposed to already and I suspect she'll really love a short top rope.

I'm no engineer and I was wondering if anybody knows of any websites or books that will help me work
out what the engineering issues are with bolting a top rope anchor to a brick wall.

Thanks,

Dylan.

rolsen1

30-Mar-2009
8:08:42 PM

I think building a free standing woodie is your best (easiest) bet. Then just attach your top rope to the top of the woodie. A 4 year old weighs 20kg if the woodie is strong enough to climb on (and not fall over and squash kids) it will hold. I top rope the kids on our rope ladder and they love it. I don't bother top roping on our woodie.

When belaying little kids you just hold the rope in your hand, no harness or belay device needed.

btw I'm not an engineer either.


Dizzy

30-Mar-2009
8:13:01 PM

Thanks for the tip. At this stage I'm thinking the woodie will be dynabolted to the wall. Maybe fixing the
top rope to the top of the woodie is the way to go.
BTW, what brand/type of harness do you use for your kids?

bl@ke

30-Mar-2009
8:25:43 PM

Hi Dizzy
I have a book on building a woody but it is only for indoors and dosnt mention anything about putting anchors into bricks. im no engineer either but i suspect hardware shops would sell anchors specialized for bricks similar to rock climbing bolts with an expanding sleeve yada yada yada...
In this book of mine it mentions something about belay bars, these are similar in shape to a shower courtain rail like this: l________l and the two sticky up bits go into the wall with some glue to keep them there (not all the way in though) and you can then chuck the rope over the bar and so-on. an advantage to this is that if your daughter goes off-line the rope will follow (as should the belayer) and this should stop a swinging fall. Another consideration would be what type of brick it is, is it just plain solid brick or is it hollow or is it cement block brick things? cos its probably not a good idea to put in an anchor into hollow bricks.
i hope this all helps :)


Dizzy

30-Mar-2009
8:40:16 PM

Hi bl@ke, thanks for the pointers - very helpful. The belay bar is a good idea, particularly for a young kid
who will no doubt want to climb all over the place. Cheers, Dylan.

stonetroll

30-Mar-2009
9:03:08 PM

Hi Dizzy . . that's a very broad queastion to ask about building onto an allready existing brick wall as there are so many variables involved.

What is the structurial integraty of the wall ?
What's the main purpose of the wall ?
What type of brick is it made from ?
Will it need extra bracing ?

It sounds like the wall is the side of building, if that's the case then 45mm x 90mm timber at 600mm centres bolted to the brick useing 100mm x 10mm dyna bolts at 500mm centres and counter sunk, would be a solid frame to take ply.

You'ld have to check out the best place for drilling into the brick as bricks come in various cross sectional patterns. Some bricks are solid but some have holes through them. Some times these holes can be 3 large holes or 10 small holes or different pattern alltogether.

There fore where you drill into the brick will depend on the type it is. It may some times be a case that actually drilling between the bricks at the perpendicular join is an better option.

If you can provide more information or some photos i may be able to give better suggestions and advice.

Good luck with your project : )

stonetroll

30-Mar-2009
9:10:58 PM

p.s For top rope anchor just bolt hangers into tour T-nuts along the top of your ply wood and equalize two for top ropeing.

rolsen1

30-Mar-2009
9:13:02 PM

On 30/03/2009 Dizzy wrote:
>BTW, what brand/type of harness do you use for your kids?

I'm always on the look out for kids sized stuff. I've got a rock empire full body harness second hand through this site. Also black diamond sell a kids harness suitable for about 7+. Cheap shoes are harder to find than harnesses.


Dizzy

30-Mar-2009
9:24:29 PM

Hi Stonetroll,
Thanks for the info about drilling into bricks etc. I'll see if I can get some good photos and send them to
you by PM - very grateful for your offer of help. You are right in guessing the wall is the side of a building
- it's one side of a 3 level house. The main part of the house is about 120 years old but I'm not sure how
old this wall is (it's probably an extension to the original house). I'll see what I can find out (I've had a
builder around recently to do work at my place and he might know some more technical info about the
wall).
Cheers,
Dylan.


pmonks

31-Mar-2009
3:08:05 AM

On 30/03/2009 Dizzy wrote:
>BTW, what brand/type of harness do you use for your kids?

I have a Petzl Ouistiti harness for my 4yo. Works fine, although when fully tightened up for her (she's a bit small for her age) the metal buckles sit on her shoulders and tend to pinch her neck a little bit when it's weighted.

Hasn't stopped her from getting into a bit of top roping and a lot of swinging around on the rope though!

devlin66

31-Mar-2009
9:07:00 AM

If you want I can knock up some drawings that can give you a guide to work to. Concrete and structures are my job so it will be easy to do. How much room do you have in plan. ie. ground space. A free standing frame can in most cases be a better set up. This way you can pivot the wall a smidge above middle height and have a fully adjustable angle without the need for any pulleys or winches. Using the brick wall would be neat but if you plan on just a vertical wall you'll get bored. Having said that mine stays at 30 deg most of teh time as it's a good training angle.

Also you might get away without having to use a top rope. Get onto ebay and check out these puppies here. Get two of these and put them side by side in a stitched up shade cloth bag. My girls jump from the top of my 4.2m woody onto these. They can be a little firm if you back slap from the very top but for the most part are an awesome setup. They have an inbuilt pump so you can adjust and reinflate with ease. I'll get some photos for you if you want.

patto

31-Mar-2009
9:54:15 AM

High brick walls are notriously weak at the top for any non vertical loads. I have heard of many deaths and injuries from people slam dunking basket ball rings attached to walls. Be careful.

grangrump

31-Mar-2009
11:19:36 AM

Yeah I agree with Patto.
Apart from baseball hoop levering down walls (when people hang off), even flower pots have pulled over brick veneer walls when hanging off brackets...
Brick walls are strong in compression only.
Be particularly scared of any climbing wall hung off the side of a house if it includes an overhang section, which can increase the outward pull on the bricks, unless properly braced.
In Canberra I can think of 2 climbing walls based on brick walls (ANU and Narrabundah). Both were specially engineered to cope, even though they are both merely vertical.
Good luck.

racingtadpole

31-Mar-2009
1:37:41 PM

If you are going to anchor to brick, in this application DONT use dynabolts, they are an expansive (also expensive) fastener and my cause internal stress in the brick when tightened, which may lead to premature failure of the wall when stressed ubder the right conditions. My weapon of choice would be Chem Anchors (Hilti, Ramset and a host of others make them in various guises and prices).
When your done can you put a few pics, I'd like to see the end result, I am considering a similar project.


Dizzy

31-Mar-2009
7:04:39 PM

Thanks to those who've posted - I'm pretty sure I've now got a much better idea about what I'll be building
in my back yard.
Cheers,
Dylan.

james

2-Apr-2009
7:06:12 AM

I came very close to pulling over an old 8ft high brick fence when I tried to anchor a slackline to it a few years ago. wasn't even close to the top - I dynabolted a short bit of angle steel on the bottom third.


atreyudelacy

2-Apr-2009
8:05:28 AM

Most people have pretty much has summarised this already, but just to reiterate.

If you call Ramset, and ask for a copy of their specifiers resource book (maybe give them the
impression that your an engineering student?) they will most likely give it to you (free). In this you can
see the capacities for a range of different anchors, and respective SWL's for shear and tension into
solid, 3-hole, and 10-hole bricks, and also concrete blockwork. However this will only give you the
capacity of the anchor, not the wall.

You will need an engineer to determine the capacity of the existing wall, however without access to a
set of structural drawings for the adjacent building then the capacity they calculate will be quite
conservative. Guaranteed. Don't just ask your local tradie for some advice (No offence to any builders
out there), but as simple as a brick wall may seem, its not, and unless you're a structural engineer,
then you don't have the understanding to really know whats going on.

In any case, I think that there are much simpler solutions. How wide is your courtyard? If its not too
wide (say much more than 5m or so) and you don't like the idea of having a some big verticals coming
down at each side of your woodie (and really no-one does), then you could run some horizontal
members at the top of your woodie (to your roof level, or first floor if you have one). this way all the
lateral loads are transferred into your house, and you only need a few dyna-bolts into the adjacent
brick wall to take some small vertical loads. I have seen this done before, and it is a MUCH better
solution. You can also use the horizontal members to put a roof over the top and keep it all dry!

paul

2-Apr-2009
10:52:17 AM

Is the wall on your courtyard part of your building? because if it isn't then your neighbour may not be too happy about you ddrilling into their wall.


Dizzy

2-Apr-2009
8:57:36 PM

I'd thought about the whole "who owns the wall?" question and I suspect a surveyor would say I own at
least part, if not all, of it. However, that's not a debate I want to engage my neighbours in and in any
event, it's probably a moot point as I'm very much thinking a free standing woodie is the way to go. It
sounds a safer and simpler bet to me, and I've got the courtyard space to house a free stander with
ease.


atreyudelacy

2-Apr-2009
9:46:09 PM

Free standing definitely sounds like the better option. Hope the construction goes well :-)

FYI - Given that the wall is part of a building, it will definitely be on the other side of the boundary
(i.e. not split down the middle of the external skin of brickwork or any pokery jiggery like that). It is my
understanding (a building surveyor will be able to answer this with more certainty) that you are able to bolt
into the wall, however works protection notices would need to be provided to the owners of that existing
adjacent structure, along with a copy of the certificate of compliance (for whatever proposed
alterations/additions may be), plans, and computations, all of which would need to be approved by the
owner of that building... i.e. a lot of effort to build a woodie IF you are so inclined as to do it by the book.
;-)

There are 26 messages in this topic.