MortarThePoint Posted Tuesday at 09:36 Posted Tuesday at 09:36 (edited) I'm making a simple porch frame to go between two walls and I am pondering between a bridle cut and a simpler to make bolt held option (M12 x 250 Stainless). The two options are at the bottom of this post (but at the top of the porch post :-). Vertical posts are 145x145 and horizontal beam is 95x195. Although it's more effort, I am currently leaning towards the bridle cut. It would prevent any light passing though a narrow gap that could open up through shrinkage. It's much more work to make though and the finished result will look identical bar any gaps. Silly? Edited Tuesday at 09:37 by MortarThePoint
MortarThePoint Posted Tuesday at 09:53 Author Posted Tuesday at 09:53 I could drill and peg at the join to fill the gap, but I'd have to be very careful not to blow through with the drill and there would still be a small unplugged gap left
garrymartin Posted Tuesday at 10:08 Posted Tuesday at 10:08 If it's a pre-existing structure, will you have enough clearance to get the bridle cut post in place?
MortarThePoint Posted Tuesday at 10:12 Author Posted Tuesday at 10:12 1 minute ago, garrymartin said: If it's a pre-existing structure, will you have enough clearance to get the bridle cut post in place? Good question. There are posts at each end of the beam which will be fixed lower down to the wall. The bridle cuts at the end would have to be like this I expect
MortarThePoint Posted Tuesday at 10:13 Author Posted Tuesday at 10:13 A concern with the bridle cut that isn't an issue with the modern fixing approach is he possibility of the post splitting due to it shrinking more than the beam
garrymartin Posted Tuesday at 10:48 Posted Tuesday at 10:48 Ah, you're making the entire frame, not trying to put vertical pieces into something that is already there. I misunderstood. In that case, definitely the bridle cut if your woodworking skills are up to it. 1
ToughButterCup Posted yesterday at 07:53 Posted yesterday at 07:53 22 hours ago, MortarThePoint said: .... It's much more work to make though and the finished result will look identical bar any gaps. Silly No: the opposite. Making it parallels learning ( for which read the 'errors' ) involved. That learning builds over time. And thus confidence. But most of all quiet satisfaction. And deep pleasure if only we ( I ?) allow ourselves to enjoy it. 21 hours ago, MortarThePoint said: .... but I'd have to be very careful not to ... There's your opportunity right there. Excellent. Do it. Photograph it. Self-build-porn that'll become. I mean you might even get a compliment from @SteamyTea ( mind you it's not Friday yet) 1
MortarThePoint Posted yesterday at 14:53 Author Posted yesterday at 14:53 Well, like Baldric I have come up with a cunning plan. It's on the far left of the options below and involves cutting an undersized notch in the beam, which gets relieved on the post using a router. It also allows a shallower notch in the beam if I cut a slot the top of the post. That slot also serves to constrain the joint laterally. It's kind of a hybrid of traditional and modern. 100mm joint with a 85mm Circular Saw depth: 100mm joint with a 50mm Circular Saw depth:
ToughButterCup Posted 12 hours ago Posted 12 hours ago Now that's neat. Remember we want photos. Instinct tells me this is maybe a bit complicated (?) One factor will be the quality of the wood; definitely a case of going to the BM and choosing the wood yourself. German chippies would solve the shrinkage problem with foam😑 1
Gus Potter Posted 2 hours ago Posted 2 hours ago On 22/09/2026 at 10:36, MortarThePoint said: I'm making a simple porch frame to go between two walls and I am pondering between a bridle cut and a simpler to make bolt held option (M12 x 250 Stainless). Are the posts just there to carry vertical load or is the beam and column acting to resist sideways sway.
Gus Potter Posted 2 hours ago Posted 2 hours ago To add a bit. If you use traditional dowels, pegs then there is an old trick that was used in Scotland. We have lots of solid stone walls lined with lathe and plaster on studs on the inside. Timber wedges were driven into the stone work mortar beds. Then they were cut flush using a string line and the studs fixed to them. That is how they got the wall plumb etc. The spelling differs, as a traditional craft, but they are commonly called Dooks. But the secret was that they would dry the Dook's often near a fire thus they had a really low moisture content. Once they were driven into the wall they expanded. A traditional wall never gets below this moisture content and thus the Dooks always hold tight. You can use the same principle if you want to peg / dowel the way you are thinking. The dowels will need to be tapered as standard, but to get them really tight dry them out in an oven first. You could of course use a modern structural glue, but that may be cheating? 1
MortarThePoint Posted 1 hour ago Author Posted 1 hour ago 54 minutes ago, Gus Potter said: Are the posts just there to carry vertical load or is the beam and column acting to resist sideways sway. Limited to the vertical forces really as I thought I would use something like a Simpson String Tie ABR to resist the otherwise unconstrained lateral motion in and out of the U-shaped brickwork. That would be in location B below. In location A I was thinking to have an bolt through an oversized hole and into the brickwork to stablise things during construction. It occurs to me that I could attach a piece of 2x2 to the wall that rides in a slot on the end of the beam. A more modern equivalent would be something like the BTALU90 but not bolted to the beam, just to the wall. That way it wouldn't constrain the beam or posts vertically which I don't want to do due to the shrinkage (admitted small along the grain). It way just be simpler to bolt the end rafters that go along the surface of the wall to the wall and their birds mouths would stop the frame tipping outwards. Some form of slip fixing through the rafter down into the beam could then constrain it from tipping inwards towards the door. Alternatively, I could bolt some wood behind the beam to constrain it, though that would be quite obvious. An advantage of having the final rafters bolted to the brickwork is that they won't move much relative to the brickwork so will limit the movement the lead flashings experience.
Gus Potter Posted 2 minutes ago Posted 2 minutes ago It looks like this is, on reflection, just an infill roof, like a small canopy that is constrained by substantial walls either side. Are we over thinking this? Vertical loads could be roof access, at a push, maybe snow dump coming off the higher roof. But the canopy looks like it has a good slope. I would go back and look at what is Architecturally pleasing, like your proposed joints earlier.
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