LEAN-TO (LT)
Used as an economical way to increase width of existing or new buildings without the additional need of a valley gutter.  Can be used with any of the 7 frame types.

LEAN-TO (LT)
A Lean-To frame has no ridge and consists of either welded-up hot-rolled rafter and column sections.  Columns and rafters are pinned at both ends.  Lean-to frames are not self-standing structures and, therefore, require a stable structure to sustain their reactions.  Frames are designed by computer analysis in accordance with accepted engineering practices.

Clearances and Reactions
Due to the broad parameters available, it is impractical to give minimum clearances and column reactions for the multiple combinations of width, spans, eave height, roof slope, bay spacing, load and codes that are available.  However, for representative samples of the information that Ceco can furnish, refer to the tables.

For actual frame clearances and reaction for any specific building, and/or for open web frames, contact the nearest Ceco manufacturing facility
 

REPRESENTATIVE
CLEARANCE DIMENSIONS
1:12 ROOF SLOPE
 

BAY SPACING  --  25ft.
ROOF SLOPE  --  1:12
LIVE LOAD  --  LL (psf)
WIND LOAD  --  WL (mph)
WIND LOAD APPLIED IN ACCORDANCE WITH MBMA (1996)

*C =  Minimum clearance other than at knee (dimension B).  All points where rafter changes shape are checked and vertical dimension to lowest of these points is given.

 **Clearances shown are approximate.  Actual clearances may be somewhat different.
Note:  1.  Clearances shown are approximate.  Actual clearances may be somewhat different.
           2.  Live loads greater than 30 pounds must be quoted.  Please contact the estimating department at your regional office.
 

REPRESENTATIVE
FRAME REACTIONS
1:12 ROOF SLOPE

NOTES:
1. Dead load equals self weight of members.
2. Wind load is applied in accordance with MBMA (1996).
3. Negative value of reaction indicates direction opposite to that shown on sketch.
4. Reactions shown are approximate only and are not exact submittal values.
5. Reactions for various load combinations may be obtained by adding or subtracting the appropriate values.
6. Forces on the foundation will act in the opposite direction to the direction of the frame reactions.

Bay Spacing -- 25 ft.
Roof Slope -- 1:12
Live Load -- 20 psf
Wind Load -- 80mph

MODIFYING FACTORS:
To obtain approx. reactions for other bay sizes, live loads, and/or wind loads use the following rules:
 

BAY SIZE: (up to 30’)	Divide all reactions shown by 25 then multiply by the bay length required.		LIVE LOAD:	Divide live load reactions shown by 20 than multiply by the live load required.
			WIND LOAD:	Multiply the wind load reactions shown by the applicable factor: 70 mph use 0.8 90 mph use 1.3 100-mph use 1.6 110-mph use 1.9 120 mph use 2.3