L ath & Plaster Supervisors Manual 2020 1 LPS (Lath & Plaster Supervisor) Certification LPS Manual Congratulations, you have passed the SMA Lath & Plaster modules. This final supervisor's exam will be more challenging. The SMA strongly recommends you watch Module 6 and become familiar with this manual before taking the LPS Certification exam. This companion manual is to prepare you for the exam. The exam is an open book exam, meaning you can and can use this manual in taking the test. The exam is segmented into sections to correspond with chapters. This manual can be used as a reference guide as you continue to supervise lath/plaster and adhered masonry work. "Knowledge with good leadership is a powerful tool to have." This manual contains generic standards and guides, technical papers, communication tips, and helps you become a better supervisor. The SMA is available to assist you when you need help. Supervisors should complete the Competent Person training for the SMA Silica Compliance Program. The key to being a great supervisor is to “always” be learning and strive to be a better supervisor. 2 CHAPTERS Page 1. COMMUNICATION a. Keys to Leadership 4 b. Duties/Checklist 5 2. BUILDING SCIENCE FOR STUCCO 6 a. Definitions/Terms 7 b. WRB- Concealed Barriers 8 c. About NF Windows 9 3. LATH & PLASTER SPECIFICATIONS a. SMA Guide Specification 10-19 b. Ceilings 20 c. Suspended Ceilings 21 4. THE BUILDING CODE (Section 104) 22 a. Control Joints 23 b. Weep Screed 24 c. Wood-Based Sheathing 25 d. Stucco Parapets 26-27 e. Cracks 28 5. ESTIMATING 29 6. FIRE & SOUND DATA 30-31 3 Keys to Leadership People are motivated by their reasons, not yours. Good leaders find ways to encourage others and must know their people; this requires trust. People want two things, Money and Happiness. Happiness may be harder to pin down, but a lot less expensive. Great leaders work to find that balance. While we say Millennials are soft, lazy, and self-absorbed, would it be more useful to think of them as just wanting “feed- back”. Cracks in stucco are always an issue, but how you communicate that message is key. “ All stucco cracks, I guarantee it” is a wrong message. “Stucco is brittle and can crack, I understand that and will take reasonable precautions to minimize those cracks." Both are factual statements, but one is good communication. Good communication is a skill set of a leader. Your words are powerful; they can hurt, inspire, or be ignored. It is up to you what kind of leader you want to be. You might think back to leaders that inspired you or possibly let you down. Common phrases can reveal what kind of leaders we typically see or train. Think about what they say. “You do not get paid to think” Or "That is an idea, let me give it some thought." “ Your pat on the back is your paycheck” Or “ Nice job on that tough detail” How would you want to be remembered? Which inspires leadership qualities? What leaders do you remember, and why? a. DEALING WITH DIFFICULT PEOPLE a. Be calm -Understand their intentions- Let them know where you are coming from - Try to build a rapport- Ignore and avoid insults-Stay focused on an issue- Escalate to a higher authority for resolution b. WHAT DO I DO NOW? a. Whenever you encounter “anything” new or odd, seek advice from other experts. c. SHIFTING THE RISK: a. Assuming you, KNOW-IT-ALL, means you are accepting all the risks. Is that smart? The GC loves this as risk shifting is an art form to many of them( See Example, page 6). 4 DUTIES & RESPONSIBILITIES DUTIES Ensuring a safe, sufficient area for productivity requires TWO prime duties: 1. CLEAR A PATH - Crews need to see a clear path to work effectively to optimize production. Hopping around/working out-of-sequence is NOT productive. Crews need at least a full day work. Including, but not limited to: a. No trenches, dangerous power lines, unsafe scaffold or other incumbrances b. Framing and Blocking is sound, dry, reasonably straight, and secure c. Other trades are not in the way of your crew being productive d. Permits/requires inspections are complete e. Is water/electricity needed? Too far away, adequate pressure? f. Windows/Doors/Penetrations are in and flashed adequately (refer to WINDOWS to learn about Design Pressures) SEE PAGE 9. * 2. SUPPLY THE CREW – All material and tools needed should be on-site BEFORE the crew starts work. a. Order the proper ratio of paper/house wrap to lath material. is paperbacked lath or rib lath required b. For masking, have the materials, plastic, tape, and knives ready. c. Make sure the machines/pumps are in working order and properly serviced. d. Make sure material (sand and cement piles) are properly placed. Should be delivered the previous day e. Review your checklist the before with the crew is there- PLAN. OTHER CHECKLIST ITEMS: • Dead loads on building (90%) to limit deflection that could crack stucco • Drywall nailed off (exterior walls), Pounding cracks green plaster • Flashing is complete and able to be integrated with your WRB • Moisture Content (MC) of all materials less than 19% • Floor line shrinkage – (watch for head-of-wall deflection with steel framing) • 1/8 inch gap - wood sheathing – See page 25 • Remind crew to notify you of any issues/concerns, do NOT just cover it up • Are safety talks complete? Use the free SMA video(s) or forms • Have managed expectations with the owner? (cracks, tolerances, texture, color) NOTE: it is strongly recommended a supervisor/foreman keep a binder or journal for each job they start, keep personal notes, dated communications, and pictures of issues/concerns. Journals can and have been used in litigation/court cases to save subcontractors and increases your value as a supervisor. 5 BUILDING SCIENCE FOR STUCCO BUILDING SCIENCE: A collection of knowledge that focuses on the analysis of physical phenomena affecting buildings. While this is needed, too many believe only “science” has validity and discount real-world or empirical evidence. Empirical evidence, blended with science, enhances the knowledge and skills needed to build more sustainable and functional structures. ARCHITECTS: Design buildings for function and aesthetics. They are responsible for costs, code compliance, and that the structure is functional for use as intended, this includes building science. GENERAL CONTRACTORS: Responsible for providing all materials and labor necessary for the construction of the design submitted. They often hire “specialized” subcontractors with expertise in a trade or specific discipline, called specialty contractors. SUBCONTRACTORS: Perform all or part of the work they are contracted or specialized in installing per the contract with the General Contractor. Must have expertise in their field. Subcontractors are NOT designers and should refrain from accepting the temptation to design. Subcontractors SHOULD point out errors and raise potential concerns related to lath and plaster. DOCUMENT the replies and proceed as directed. Refusal to perform duties per your contract should be limited to severe issues, such as Life/Safety concerns just because YOU do not like it is not valid and could put your firm at future liability. EXAMPLE: A designer specifies a specific flashing product or design. You prefer another product or design. You put in a submittal request to use this alternate product/design. The architect responds “Install as specified”. Because you feel you a smarter, you press the issue. Maybe even refusing to warranty your work unless"your" design is accepted. The designer caves in and lets you get to use the product/design you demanded. You WIN, or did you? If a problem occurs, that designer will likely pull out your communication and remind you, Compliments: Western Exterminator YOU are responsible now. You have essentially given them the hammer to pound you late. The SMA has seen this before. Be smart, make suggestions, use industry documentation (ASTM, SMA or regional groups), then DOCUMENT the response and directives (such put a copy of the email in your journal) then follow directions. It is your duty to point out concerns, not to design. STUCCO PROPERTIES • Cement plaster properly mixed and applied is water-resistant (Data available on request) • STRENGTH: Compressive 1,500 to 2,800 psi – Tensile 200 lbs -Thermal Resistance .15 • WEIGHT: ½ inch 5.89 lbs – ¾ inch 8.85 lbs – 7/8 inch 11.78 lbs • Noncombustible – 0 flame spread – 0 Smoke Developed • Cement Plaster is vapor permeable, ratings vary on mixes, and the finish/paint coat applied. 6 DEFINITIONS-TERMS AIR BARRIER: A material used to prevent airflow. Compliance should follow the International Energy Conservation Code (IECC). Below are excerpts from 2012 IECC Chapter 4 C402.4.1.2.1 Materials: air permeability no greater than 0.004 cfm/ft² OR the follow materials are deemed to comply: 3/8 inch Plywood, OSB, Extruded Polystyrene, Foil back Polyisocyanurate, Spray foam with a density 1.5 or greater, ½ inch gypsum or cement wallboard, Portland cement plaster at or + 5/8 inch thick, concrete, concrete block and sheet aluminum. Assemblies: air permeability no greater than 0.04 cfm/ft² OR the following assemblies are deemed to comply: CMU with two coats paint, Portland cement plaster min. ½ inch thick (all joints must be sealed). CEMENT (HYDRAULIC) a cement that can harden under water – AKA Portland Cement CLASS A FIRE RATING: Product with a flame spread 25, or less and smoke developed rating 50 or less CONTROL JOINT: A one-piece trim accessory with less than ¼ inch movement in one direction only CRACKING: A form of stress relief in plaster. Brief explanations of various cracks: re-entrant cracks are at corners of windows, etc.