Do I need to install rigid insulation in the bottom of a walk-in refrigerator before I install tile?
I am being hired to remove the failing metal floor and install quarry tile in the bottom of a commercial walk in refrigerator. The existing floor has 4″ of insulation, then plywood and then metal floor on top of the wood. I believe the existing insulation is in very poor condition and possibly wet and I am planning to remove all of it. This is in a restauraunt in southeren California which is on the second floor of a commercial building where there is a structural slab as the foundation and there is occupied space on the first floor below. The existing metal floor inside the refrigerator is overall about 5″ thick. There is existing quarry tile at the entrance into the refrigerator and the metal floor ramps up inside the rrefrigerator. I have had conflicting recommendations from refrigeration contractors that insulation is and is not necessary in this application. The refrigerators are set for 34-38 degrees. It is not a freezer.
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Replies
Jim,
My instinct (and building science knowledge) tell me that insulation is necessary. But I have no background in the field of walk-in refrigerators, so I don't know what standard practice is.
If I were involved with this job, I would want: (1) an adequate thickness of rigid foam insulation above the slab; and (2) a waterproof membrane to make sure that spills don't reach the concrete. Moreover, I would want the floor assembly to be detailed by an engineer.
Jim,
I've built several walk in coolers for restaurants. The floors were detailed much like the walls, with several inches of rigid insulation sandwiched between the interior and exterior finishes. They are usually under-insulated from an energy conservation perspective, but there isn't much point in beefing up the floor if the walls and ceiling are not comparably thick.
If it were me I'd put down two inches of XPS, PT plywood and a de-coupling membrane under the tile, which would also help protect against the moisture from the frequent mopping of the floor.
谢谢Malcomb和Martin。您的知识极大地帮助了我。我认为这种方法就是我要做的。告诉我您对我的特定计划的看法。我认为我的方法是首先在整个地板上连续放下1英寸厚的刚性绝缘材料。在该层的顶部，我将在周围铺设经过平坦的2x4，然后再加上同一刚性绝缘的1.5英寸层。该层上面的3/4胶合板拧到卧铺。在这一点上，如果将冷却器硅在侧面的侧壁上固定在凉爽的侧壁上并拧到胶合板上，我将在周围安装6 x 6不锈钢L-金属。然后，我将在胶合板的顶部和L-Metal上防水，以使任何水分永远不会进入胶合板或绝缘层。现在，我将安装一个1.5英寸厚的电线增强砂浆床，然后在其上安装采石场瓷砖。我还将安装采石场瓷砖架6英寸高6英寸高，从本质上讲，它将覆盖在周围的不锈钢L-Metal上。灌浆将是Laticrete环氧灌浆。
我对您现在所拥有的猜测是，您所说的5英寸厚的金属地板实际上是金属面的sip（结构绝缘面板）。5英寸厚度中的大多数是绝缘材料，其顶部和底部相对较薄。如果我对此我对，现在有8-9英寸的绝缘材料。从8-9英寸的绝缘材料到没有绝缘材料将导致电力消耗大大增加，高地板温度会导致地板上的食物变质，以及地板下木头的水分问题。我建议以类似厚度的高密度EPS泡沫。