Carport MWRFS or Open

[engineerED930]

Hello all,

I am calculating wind loads on a carport in Florida. All of the walls are open, but the gable ends are going to be covered with sheathing and siding. Would this be considered an open structure or a MWRFS?

 

[driftLimiter]

Why not both? See ASCE7 27.3.2 and Figure 27.3-4

 

[engineerED930]

Why not both? See ASCE7 27.3.2 and Figure 27.3-4

I read it over, does that mean I would apply free or obstructed flow? in this case obstructed is less than 50%, so free.

 

[driftLimiter]

Yep footnote 2 doesn't leave a lot of room for interpretation. If you have over 50% permanent blockage below the canopy in the direction of consideration then you go obstructed, if not then free.

 

[engineerED930]

Yep footnote 2 doesn't leave a lot of room for interpretation. If you have over 50% permanent blockage below the canopy in the direction of consideration then you go obstructed, if not then free.

Thank you for your help, drift.

 

[DanKile]

If you are sheeting more than 20% of the wall area of a wall, you no longer have an open building (26.2).

The obstruction to flow is for what is "inside" the building (compressors, hay bails, RVs). You would probably need to check both free flow and obstructed for a carport.

 

[engineerED930]

If you are sheeting more than 20% of the wall area of a wall, you no longer have an open building (26.2).

The obstruction to flow is for what is "inside" the building (compressors, hay bails, RVs). You would probably need to check both free flow and obstructed for a carport.

The lateral force would just be the wind pressure (P) multiplied by the area of the sheathing correct?

 

[ANE91]

The lateral force would just be the wind pressure (P) multiplied by the area of the sheathing correct?

I’d also include half the posts.

 

[engineerED930]

I’d also include half the posts.

Thank you

 

[engineerED930]

Thank you all for your input.