Browse Forums Outdoor Living 1 Feb 12, 2012 4:23 pm Hi folks. I'm building a light, shade-cloth-covered horizontal pergola down the drive, which will serve as a carport. Dimensions are 5 metres x 2.8 metres. It will be attached to the side of the house via a ledger, which I have bolted into the brick using 60mm mungo plugs. The ledger comprises three separate lengths of pine (75mm wide x 35mm deep), necessarily interrupted by a drainpipe located vertically down the wall about 745mm from the left edge. The shortest length of pine I'm using for the section of the ledger to the left of the drainpipe is only 740mm long. I've fixed this to the brick using 2 mungo plugs. The two pieces of pine comprising the other section of the ledger to the right of the drainpipe are each a bit under 2m long. I have used 3 evenly spaced mungo plugs in each piece to affix to the brick wall. It has recently occurred to me that I might not have used long enough mungo bolts. At 60mm each, they go through the 35mm width of the ledger, thus penetrating the brick by 25mm. They tightened up very well and feel rock solid, but I am now concerned that 25mm into the brick might be a bit iffy as a means of supporting the pine rafters. I am using relatively light rafters (90mm x 35mm pine), about 2.8 metres in length. The left end rafter will be borne by the small section of ledger to the left of the drainpipe, the right end rafter by the ledger on the right, and another middle rafter by the ledger section in the middle. I may later add two more rafters to either side of the middle one, which would mean that each of the two longer ledger sections would be bearing two rafters. There will also be battens flush to the brick wall and fixed to the top edge of the rafters, to which I will be attaching that side of the shade cloth. I am not anticipating adding another parallel batten down the centre, but I may do so, depending on how the shadecloth ******. I'd much appreciate some advice by savvy folk as to: 1. Whether I need to drill further into the brick and replace the current 60mm bolts with 80mm ones. In other words, increasing penetration of the bolt into the brick to 45mm, rather than the 35mm of the current bolts. 2. The end rafters will be fixed flush to the extreme left and right ends of the ledgers, respectively. In the case of the left section of the ledger, the left mungo plug is 13mm in from the end, and ditto the right mungo plug on the right section of ledger. Is the location of these mungo plugs relative to the end rafters any concern re the load bearing capacity of the ledger? I imagine the strongest part of the ledger sections would be the areas between the mungo plugs that fix them to the wall. So, if I'm fixing the rafters flush to the ends of the ledger, the load will be off to the sides off the left and right mungo plugs respectively. Does this present any sort of weight bearing issue? Sorry about the protracted description, but I've been trying to give a clear picture of the situation, and include all relevant info. Hopefully, the pain has been worth the gain! Thanks. Ross Re: Mungo plugs queries re pergola ledger 2Feb 13, 2012 5:28 pm For what you describe I'd be installing the 10mm x135mm ultra long plugs. Even the 100mm plugs have a maximum material thickness of 10mm, so not enough for your 35mm plate. It may seem like overkill but the 80mm plugs are nowhere near long enough. I'd probably come in around 50-100mm from each edge of timber for the first fixing. For your 2m lengths if you come in 100mm and then fix at 600mm it works out evenly. You are always better to have too many and over engineered fixings, than have it come down on someones head. Accessible Carpentry & Cabinets accessiblecarpentry@gmail.com accessiblecarpentry.com.au https://www.facebook.com/pages/Accessible-Carpentry-Cabinets/583314911709039 Re: Mungo plugs queries re pergola ledger 3Feb 14, 2012 12:46 pm chippy You are always better to have too many and over engineered fixings, than have it come down on someones head. Absolutely, chippy! Couldn't agree more. Just some clarification, please. 1. When you say you'd come in 50-100mm from each edge of timber for the first fixing, do you mean the first mungo plug fixing the ledger to the wall, or the first pergola rafter fixed to the ledger? 2. The bricks are 100mm across, so with the ledger being 35mm thick, I'd need to use 100mm mungo plugs, surely? Much longer and they'd go right through the brick and out the other side. 3. Since you've indicated that no length of mungo bolt usable in this situation is long enough to support a ledger 35mm thick, is there an alternative masonry fastener you'd recommend? I was put off dynabolts in favour of mungos by a tradie friend, who reckons dynabolts can cause brick to shatter and are too hard to remove (if that is ever necessary). I've checked out anka plugs, but these seem made for attachment to cavity bricks, rather than solid bricks as in my case. So, do you have another recommendation, pls? (NB: I don't want to use chemset anchors). Cheers and thanks for your help. Ross Re: Mungo plugs queries re pergola ledger 4Feb 14, 2012 5:24 pm Hi Ross Start you fixings about 50-100mm in from the ends of your plate/ledger. I'd still use the 135mm plugs. The hole will go right through the brick but I'm assuming it is a cavity wall so you won't see the back off the brick. As bricks are full of holes this ensures you are holding in as many webs of the brick as possible. If you are concerned about going through the brick then drop down to the 100mm ultra plugs. Accessible Carpentry & Cabinets accessiblecarpentry@gmail.com accessiblecarpentry.com.au https://www.facebook.com/pages/Accessible-Carpentry-Cabinets/583314911709039 Hi, I'll be starting on my verandah repair soon - replace ledger, rafters, roofing iron, flashing etc. (fascia board already done). My question is about the timber ledger… 0 3323 1 is free to air and the other 2 are for cable TV all of them completely useless in 2024 1 2257 There is a whole lot more to know than just the answers you seek but they are a good start. Overflow outlets have a mosquito proof mesh. These… 3 8422 |