25-BM05 QA.pdf

RFB 25-BM05

COLUMBUS STREET WATER TOWER REPAIRS

Questions & Answers Questions deadline 3/25/2025

Answers Posted by 3/31/2025 (answers in red)

1. Will it be possible to close off the road to access the water tower?

Yes, partial road closures can be accommodated but a traffic plan must be submitted to the Public Works Department three (3) weeks before closure is needed.

2. What are the locations for storing materials and supplies?

Materials and supplies can be stored at 201 South Bristol Street, which is location is three (3) blocks from the job site.

3. Where is the water connection located?

Water connection is by Sun Prairie Public Works at 201 South Bristol Street but if a closer source is needed a meter can be placed on a nearby fire hydrant for usage.

4. What is the type of the replacement stones?

Limestone that best matches the existing ones.

5. Is there a specification for the type of mortar to use? (Lime, Type O, Type N?)

The type of mortar used to repoint mortar joints in the stone should be Lime mortar, mixed onsite to match the current historic appearance, texture, pointing profile and formulation of existing mortar.

6. What are the measurements and square footage of the water tower? What is the total square footage for the inside?

Total Block Height = 60’ 4,161 sf Interior square footage 3780 sf

7. What is the method of removal to be used to remove the old mortar?

Grind or chisel out mortar joints to a depth of 2-2 ½ times the width of the joint or deeper until sound original mortar is located. The minimum depth of thin joints is 3/4″.

Once removed, any accumulated dust or debris should be cleaned/removed to ensure sound bonding on joints. Anticipated work should be completed without damaging the existing masonry units and building.

8. What are the dimensions of the windows?

Window dimensions are 58”x 22”.

9. For the ventilation, do you want the vent cut in the bottom of the existing door or the stone wall?

The existing door.

10. Do you have an address for the Architect or Engineer?

No

11. It states to spot clean inside and outside: What type of cleaner is allowed to be used? Washing with a hose and brush or a power washer?

Acceptable means of cleaning can include laser cleaning, steam/mist cleaning, poultice cleaning, hose and brush, and/or power wash with low pressure to spot clean existing limes stone and brick. The method used should be completed with the best historical preservation practices to avoid erosion of stonework.

12. Apply consolidation product to existing stone to bind friable and delaminating portions to the solid backup materials: What product is to be used? Do you want this on all inside and outside surfaces?

Calcium Hydroxide should be used and only on the exterior.

13. Replace the existing windowsills: Do you want a new masonry wash put on? Or remove the stone and put in a flashing? New stone?

New wash put on and where needed, stone replaced with new ones that best match the existing ones.

14. Replace failed steel cross beams: Do you want the whole cross beam replaced or just the ends that are corroding away? If so, how many?

There is a total of Eight (8) cross beams with anticipated service to included repair or replacing the ends of the corroded beams.

15. Flashing at the catwalk ladder opening: Do you want rubber and an SS pan flashing with a drip edge installed?

Yes

16. Sealing the perimeter of the catwalk with silicone: Do you want it sealed where the catwalk/steel goes into the stone?

Yes