Four post in a small garage

[kent olsen]

At the suggestion of Funracer:

My garage is also a small two car with rafters about 8' off the floor. I spent several weeks with a tape measure and paper looking for how to get a 4 post lift in my garage.

Two obvious problems: The rafters and the retractable main door. The tallest of my cars is the Classic Mini at 50". So I needed to get the lift up high enough to drive the Mini underneath. The lift vertical posts have numerous lock spaces to stop and hold the lift. In the picture you will see I cut a notch out of my rafters, resupported the horizontal ends of the rafter and then took the cut piece and reattached it higher up near the roof. That extra space gave me enough height to get the Mini under the lift tracks when it was elevated. So the lift will only be about half way up.

Then next problem came when I started to build the lift. The rear vertical post was to high and the garage door couldn't open because the post was in the way. Actually the supplier did have a unit with shorter vertical posts but I didn't see that. I ended up taking the post to a friends who had a very big hacksaw and cut about 18" off the end. Then I had to go to a logging supplier who cut the cable shorter for me.

Once it was all together everything was right until I put the Porsche on the lift. Even with the car well forward the garage door would hit the ducktail. Well the opener has a adjustment were you can stop the door before it gets to the end of the track. So I just restricted it when it got close to the ducktail. Still opens enough that I can walk under the door when it's open.

[TwoBluPorsches]

My garage was similarly challenged.
I modified the trusses after I got an engineer to work out the details.
(I wanted to get building permit and inspections so I won't have any issues down the road when I sell the place)

My garage door now uses a shaft drive opener and the door opening limit is 52 inches.
High enough to drive either 911 through the opening.

It's a bit of a duck to walk in

[Funracer]

Originally Posted by TwoBluPorsches

My garage was similarly challenged.
I modified the trusses after I got an engineer to work out the details.
(I wanted to get building permit and inspections so I won't have any issues down the road when I sell the place)

My garage door now uses a shaft drive opener and the door opening limit is 52 inches.
High enough to drive either 911 through the opening.

It's a bit of a duck to walk in

I was told my trusses could not be modified. They can only be replaced with ones built with an open middle. A much bigger project. I need to find a different engineer.

[pete3799]

I'm no engineer but those cut rafters scare me.

[mepstein]

Originally Posted by pete3799

I'm no engineer but those cut rafters scare me.

I agree. That can’t be good.

[proporsche]

i`d say repair it back so it is a solid structure.Get yourself scissor lift ..no need 4 points on 911.
it does look scary

ivan

[blucille]

from that photo, it looks like it would be "easy" (from my perspective- sitting at a keyboard) to raise the whole roof by 6"

[deemsriddle]

If you try to sell the house, that will never pass inspection. This is a problem if you are selling the house to someone who is financing it. A local building inspector would condemn the structure as unsafe. Clearly this was done without permit and the inspection that would have been required. If something happens and you were hurt, your health insurance would probably deny paying a claim. If someone else were hurt, then your homeowners insurance could likewise refuse payment. Either way, you could be bankrupt. I hint to the wise, let someone who knows something about structure, design a repair and do it.

[Dpmulvan]

Originally Posted by proporsche

i`d say repair it back so it is a solid structure.Get yourself scissor lift ..no need 4 points on 911.
it does look scary

ivan

Repair it back??? The whole roof will need to be taken off. You have sheathing nailed to rafters and shingles or roofing nailed to sheathing.

[proporsche]

Originally Posted by Dpmulvan

Repair it back??? The whole roof will need to be taken off. You have sheathing nailed to rafters and shingles or roofing nailed to sheathing.

that is what i meant..fix it it up so it is safe...
Ivan

[kent olsen]

I figured this would draw some interesting comments. But that's not sheathing. It's sheets of insulation nailed onto the walls and roof. Just an attempt keep the garage a little warm in the winter when I'm tinkering. If I lived in a climate with lots of snow the strength of the roof would be an issue, but I live in Oregon and we rarely have more than 3-4" of snow for 1-2 days. The strength of the rafters is just moved up a foot of two so that's an angular difference and without a lot of snow weight I don't feel it's significant. Just the opinion of an old car nut who flew airplanes around the world for 45 years.

[pmax]

No structural engineer here but it just appears the shorter section of the cut horizontal pieces don't serve any function other than adding load to the rafters, unless you're planning to use that for more storage !

[brshap]

Structural engineer here. Those trusses are extremely unsafe.

[PeteKz]

100% agree with Ivan and brshap. That compromised roof structure is a cave in looking to happen. There are manufactured roof trusses that "V" up in the middle for more overhead space, but the bottom beams go all the way to the edges and are strongly tied together. Those pieces you screwed into the upper beams are not solid connections.

I've lived in the PNW awhile too, and I can assure you that you will get a heavy snow load someday, in accordance with Murphy's Law.

[targa80]

Question?: Do you get heavy snowfall in the winter in Oregon?

[rwel]

Originally Posted by kent olsen

I figured this would draw some interesting comments. But that's not sheathing. It's sheets of insulation nailed onto the walls and roof. Just an attempt keep the garage a little warm in the winter when I'm tinkering. If I lived in a climate with lots of snow the strength of the roof would be an issue, but I live in Oregon and we rarely have more than 3-4" of snow for 1-2 days. The strength of the rafters is just moved up a foot of two so that's an angular difference and without a lot of snow weight I don't feel it's significant. Just the opinion of an old car nut who flew airplanes around the world for 45 years.

I agree with those who have deemed your truss modifications inherently unsafe, what with the unknown load-bearing capacity and the chosen fasteners (screws I guess?) Hate raining on anybody's parade...not what this forum is for IMHO...but you posted the pictures, so you kind of asked for it.

Like the original poster, I too am "an old car nut who flew airplanes around the world for 45 years". Unlike the poster, before USAF pilot training, I got a BS in civil engineering, and did my share of truss and beam load calculations.

[MBAtarga]

What is needed is a scissor truss design. Two videos below show a modification that could be done and still provide the correct roof reinforcement.

[PeteKz]

Originally Posted by targa80

Question?: Do you get heavy snowfall in the winter in Oregon?

Oregon is a big state, as is Washington. The climates vary greatly from coastal to high mountain to desert, so yes, there are places of very heavy snow every year. Those have big ski areas.

But let's just talk about the areas like Portlandia and Willamette Valley, since that's where the great majority live: Heavy snowfalls of say, 12 inches or more, are rare, but they do happen. Last year, we had a dump of snow in early April that was over 12" in some parts of the Portlandia metro area, and it was fairly wet snow, which weighs more than drier snow.

[kent olsen]

Certainly opens the door for comments. As far as strength goes when I assembled my 4 post lift I ran a line from my overhead winch (on the other side of the garage) thru a pully and then down to my car trailer that I had carried the new lift home. The heaviest side of the lift is the side with the cables, it weighs about 750lbs. My two friends and I watched very carefully for any stress on the new rafters as we lifted the ramps off the trailer and no one noticed any stress on the rafters/roof. There are a couple more supports I added to the upper roof not visible in the picture.

Anyway I really love my lift, at my age (79) I don't like crawling around under a car. This way I just lift up the car, get on my swivel stool and slide under for what ever I want to mess with. The only inconvenience so far is if you want to take off a wheel. Then you have to slide a floor jack under the car and the ramp to get it high enough to place a jack stand and pull the wheel.

[JSV798]

As someone who has built garages I would double up on the bolts holding the ends of your repositioned rafters and add another rafter above and put two bolts in each end of those too. Then I would add an upright in the centre (short piece of timber) to the apex of the roof. And I would remove those cut off pieces of wood - in fact use those for your uprights in the centre.

Roy