Fastening pergola roof beams to rafters/house

[KJD]

Hi, trying to understand what would be the simplest and best way to anchor a pergola/patio roof (want it to support plexiglass 1.5m out) into the house rafters 220x45.

I have some drawings in progress from the Swedish Wood guide for patio roofs, but I’m considering if I could replace the beam against the house with some type of joist hanger that attaches directly to the rafters. I’ve been advised to look at “Simpson Strong-Tie Gerw” (there must be many different brands)... basically a sitting plate with a small angle to hold the beam at the bottom, but unsure if I can do without the load-bearing beam in the proposed drawing for this kind of solution. Or how I would need to modify the inputs for the Swedish Wood calculator if so?

Is this understandable?

Dimensions attached below. In the photo with spoken language, red marks the rafter (encased) and yellow indicates the intended pergola beam.

 

[KJD]

Hi, trying to understand what the simplest and best way would be to anchor a pergola/patio roof (want to support plexiglass extending 1.5m) in the house rafters 220x45.

I have some drawings in progress from the Swedish wood guide for patio roofs, but I'm considering if I could replace the beam against the house with some form of joist hanger that attaches directly to the rafters. I've received a tip about "Simpson strong tie Gerw" (there are surely many different brands) .. essentially a seat with a small angle to hold the beam at the bottom, but unsure if I can dispense with the beam in the design proposal for such a solution. Or how I would need to modify the input values for the Swedish wood calculator?

Does this make sense?

Dimensions attached below. In the photo in common language, the red marks the rafter (clad) and yellow the intended pergola beam.

Sorry, writing/typed from mobile and see lots of crazy spelling above.

I don't believe in using the lap bracket anymore since the pergola will have a different angle than the roof of course. Didn't think of that 🤓.

Our house has the problem that there is no space between the eaves and the top of the window. So can't fit a beam in the traditional way.

I'm considering if a better solution would be to attach a beam directly to the end grain of the rafters, for example using angle brackets (but that does require some dismantling of the clad panel under the eaves).

Then I could do as usual and extend the roof joists in alignment to the pergola from this beam.

Tried to draw a bit. Can this be understood? Unsure, but interested in opinions.

 

[Peter787]

Sorry for writing/from my mobile and seeing lots of crazy spellings above.

I don't believe in using ger-ink anymore as the pergola will have a different angle than the roof, of course. Didn't think of that 🤓.

Our house has the problem that there is no space between the eaves and the top of the window. So, I can't fit a support beam in the traditional way.

I'm considering if a better solution would be to attach a support beam directly against the end grain of the rafters, e.g., using angle brackets (but this does require some disassembly of the enclosed panel under the eaves).

Then, I could do it as usual and project roof rafters in the same line to the pergola from this support beam.

I tried to sketch a bit. Can this be understood? Unsure, but interested in opinions.

Why not have a mechanical workshop bend/weld an angled plate, possibly with an underside too, to distribute the load over a longer distance on the rafter and pergola beam?

 

[KJD]

That could be a plan, but then the vision of dedicating the vacation to family crumbles a bit.

But you're thinking it would be too much of a peak load, I guess?

I just saw a more direct solution that's very close to the standard solution with a ledger on the facade. I have 12cm directly above the windows… although the slope of the rafter takes this space, I could put up a ledger here, then cut up the panel that encloses the rafters, and place my pergola roof tile directly on it.

Made a new image: red = ledger on my remaining 12cm facade, yellow = cut in panel, blue = pergola roof rafter.

This should be standard, although I might get the dimensions depending on how strong/weak the ledger becomes here.

 

[Peter787]

That could be a plan, but then the goal image crumbles a bit, to sanctify the family during the holidays.

But you think it will be too high a point of load then I guess?

I just saw a more straightforward solution that is very close to the standard solution with a support beam on the facade. I have 12cm available directly above the windows... however, the slope of the rafters takes this up, but I could install a support beam here, then cut the panel that encloses the rafters, and go on with my pergola roof tile directly onto this.

Created a new image: red = support beam on my 12cm facade that remains, yellow = cutting in the panel, blue = pergola roof batten.

This should be standard, though I might have the dimensions depending on how strong/weak the support beam becomes here.

I don't quite understand what you mean by 1.5m plexiglass, is it the entire width of the pergola, i.e., no posts on the outermost part?
Depending on the surroundings, it can create a strong lifting moment when it’s windy.
In any case, the support beam is not needed if you can attach the pergola's roof beams directly to the house's rafters, for instance, by using longer metal fittings that maybe go 30 cm into the rafters instead of the small joist hangers and angle brackets you had drawn, if you have posts at the far end, it will definitely work.

 

[KJD]

I don't quite understand what you mean by 1.5m plexiglass, is that the entire width of the pergola, i.e., no posts at the outermost parts?
Depending on the surroundings, it can create a strong lifting moment when it's windy.
In any case, you don’t need the carrying beam if you can attach the pergola’s roof beams directly to the house’s rafters, for example by using longer metal brackets that perhaps go 30 cm into the rafters instead of the small beam shoes and angle brackets you had drawn, if you have posts at the outermost parts, it will definitely work.

Ok, good input. I've scanned the market for brackets but haven't found much in that size.
I will have posts at the outermost parts and a carrying beam there. The initial plan was 6 m wide (along the house) and 3 m deep (perpendicular to the facade), but I've scaled it down to 2 m deep. Whole height is 3 m, due to the basement/semi-souterrain. So certainly much lift force. (It gets quite windy here, also the west side).

The primary function is to reduce solar radiation (many windows) and provide sun protection.

Secondary is a little protection on a summer evening, with some rain splash.

 

[z_bumbi]

The classic is a board/ruler on each side, but a slightly thicker sheet per side should also work. Someone who can calculate can provide the exact thickness.