Home>Discussions>INTERIORS>Molding & Carpentry>Interior brick walls covered with plaster or concrete I think....Need avise!
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Clarence
Re: Interior brick walls covered with plaster or concrete I think....Need avise!

The wood blocks in the brick wall were there when the wall was constructed they are called nailers and used to hols furring to the brick walls than wood lath was nailed to the furring.
The wood blocking should be either 16 inch or maybe up to 24 inches apart horizonal and up to 4 Ft vertical.
The other type of nailers were called mule boards and were placed in place of a brick course horizonally about every 4 ft. and furring strips nailed to the mule boards than the wood lath.
As for repair to the old Historical brick for repointing the joints and parging I would recommend that a soft mortar be used.
I would say 350 PSI Type O " Mortar but no stronger than 750 PSI Type " N " Mortar.
You could also use NHL mortar ( Natural Hydralic Lime )it comes in Type 2 3 & 5 2 being the lower psi

bwalton41073
Re: Interior brick walls covered with plaster or concrete I think....Need advise!
Clarence wrote:

The wood blocks in the brick wall were there when the wall was constructed they are called nailers and used to hols furring to the brick walls than wood lath was nailed to the furring.
The wood blocking should be either 16 inch or maybe up to 24 inches apart horizonal and up to 4 Ft vertical.
The other type of nailers were called mule boards and were placed in place of a brick course horizonally about every 4 ft. and furring strips nailed to the mule boards than the wood lath.
As for repair to the old Historical brick for repointing the joints and parging I would recommend that a soft mortar be used.
I would say 350 PSI Type O " Mortar but no stronger than 750 PSI Type " N " Mortar.
You could also use NHL mortar ( Natural Hydralic Lime )it comes in Type 2 3 & 5 2 being the lower psi

Thanks Clarence!

Just one last question can i remove the small blocks since I will not be nailing anything across the wall? And most importantly can I skim coat the entire walls using the mortars you listed above? I would like a smooth flat surface when I begin framing the walls. Also, if skim coating is possible do you have any suggestions to make the job easier?

keith3267
Re: Interior brick walls covered with plaster or concrete I think....Need avise!

I think you got a good answer on the brick issue, your walls should be several layers thick. Sometimes plaster was applied directly to the brick, but that was probably done later to the house by someone that did not know what they were doing. It is not a good idea, the brick needs to breath a little.

The green coating inside your copper pipes is normal. It is actually the copper forming a thin layer of copper oxide, aka corrosion. Once the layer forms, it protects the copper under it from further corrosion. It also acts as a biocide keeping your water safer to drink. If the copper pipes are over 50 years old, you might want to replace them anyway. The biggest concern with old pipes is the lead used in the solder back in the old days.

The drains are usually cast iron. The nice thing about cast iron is that it is a great noise suppressor. Due to cost, your plumber will want to use PVC. If the vertical sections of the cast iron are in good shape, and they usually are as they don't have standing water or sewage in them, then see if he will reuse them and only replace the horizontal sections.

As for the vent (fume) lines, it is best to use them unless it is just impossible. Your tub and sink can share the vent line where it goes through your roof. You generally make the connections up in the attic. Your plumber will know how to do this.

bwalton41073
Re: Interior brick walls covered with plaster or concrete I think....Need avise!
keith3267 wrote:

I think you got a good answer on the brick issue, your walls should be several layers thick. Sometimes plaster was applied directly to the brick, but that was probably done later to the house by someone that did not know what they were doing. It is not a good idea, the brick needs to breath a little.

The green coating inside your copper pipes is normal. It is actually the copper forming a thin layer of copper oxide, aka corrosion. Once the layer forms, it protects the copper under it from further corrosion. It also acts as a biocide keeping your water safer to drink. If the copper pipes are over 50 years old, you might want to replace them anyway. The biggest concern with old pipes is the lead used in the solder back in the old days.

The drains are usually cast iron. The nice thing about cast iron is that it is a great noise suppressor. Due to cost, your plumber will want to use PVC. If the vertical sections of the cast iron are in good shape, and they usually are as they don't have standing water or sewage in them, then see if he will reuse them and only replace the horizontal sections.

As for the vent (fume) lines, it is best to use them unless it is just impossible. Your tub and sink can share the vent line where it goes through your roof. You generally make the connections up in the attic. Your plumber will know how to do this.

Keith,

So not a good idea to cover entire brick wall with mortar? I should just fix all the bad spots?

As far as the fume lines what about the mechanical ones I heard about that hook up to the septic line at the sink and tub?

Clarence
Re: Interior brick walls covered with plaster or concrete I think....Need avise!

Yes you can remove the wood blocks and fill with the type O mortar.
As for skimming the bricks I agree it not recommended to cover or plaster the interior with gypsum plaster or a very hard dense coating like hard portland cement.
But if you use the typo O mortar at 350 PSI it will breath as the mortar will be compatable with the old soft mortar existing in the joints know.
If you can't find the Type O Mortar use the NHL 2.
Do not use Type N from the local supplier.
If you are close to Georiga you can get a real good tope O from A.W. Cook Hoschton, Georgia. 30548 Ph # 706-654-3677.
I have use 142 50 # bags as of this mounth it is great and works well and will skim smooth no trouble.

Clarence
Re: Interior brick walls covered with plaster or concrete I think....Need avise!

Yes you can remove the wood blocking and fill in with the type O mortar.
I agree that direct applacation of a gypsum or hard dense mortar is not acceptable as a skim coat.But type O mortar of no more than 350 PSI wuold be ok as it is breathable and compatable with the existing bricks and mortar.Do not use a type N mortar from the local supplier.
THe NHL 2 would work very well.
If you need a good Type O and are close to Georgia check with A.W. Cook Hoschton, Ga. 30548 Ph# 706-654-3677

bwalton41073
Re: Interior brick walls covered with plaster or concrete I think....Need avise!
Clarence wrote:

Yes you can remove the wood blocking and fill in with the type O mortar.
I agree that direct applacation of a gypsum or hard dense mortar is not acceptable as a skim coat.But type O mortar of no more than 350 PSI wuold be ok as it is breathable and compatable with the existing bricks and mortar.Do not use a type N mortar from the local supplier.
THe NHL 2 would work very well.
If you need a good Type O and are close to Georgia check with A.W. Cook Hoschton, Ga. 30548 Ph# 706-654-3677

Clarence,

Awesome news. I think I have enough info now to jump back in. Thanks for all the great advise.

bwalton41073
Re: Interior brick walls covered with plaster or concrete I think....Need avise!
Clarence wrote:

Yes you can remove the wood blocking and fill in with the type O mortar.
I agree that direct applacation of a gypsum or hard dense mortar is not acceptable as a skim coat.But type O mortar of no more than 350 PSI wuold be ok as it is breathable and compatable with the existing bricks and mortar.Do not use a type N mortar from the local supplier.
THe NHL 2 would work very well.
If you need a good Type O and are close to Georgia check with A.W. Cook Hoschton, Ga. 30548 Ph# 706-654-3677

keith3267 wrote:

I think you got a good answer on the brick issue, your walls should be several layers thick. Sometimes plaster was applied directly to the brick, but that was probably done later to the house by someone that did not know what they were doing. It is not a good idea, the brick needs to breath a little.

The green coating inside your copper pipes is normal. It is actually the copper forming a thin layer of copper oxide, aka corrosion. Once the layer forms, it protects the copper under it from further corrosion. It also acts as a biocide keeping your water safer to drink. If the copper pipes are over 50 years old, you might want to replace them anyway. The biggest concern with old pipes is the lead used in the solder back in the old days.

The drains are usually cast iron. The nice thing about cast iron is that it is a great noise suppressor. Due to cost, your plumber will want to use PVC. If the vertical sections of the cast iron are in good shape, and they usually are as they don't have standing water or sewage in them, then see if he will reuse them and only replace the horizontal sections.

As for the vent (fume) lines, it is best to use them unless it is just impossible. Your tub and sink can share the vent line where it goes through your roof. You generally make the connections up in the attic. Your plumber will know how to do this.

Keith,

Keith,

Would like to thank you as well for all the plumbing advise. I like the idea of branching off the main one that runs up from the toilet. My plumber replaced the cast iron septic line that ran upstairs with PVC, but is going to somehow connect the new PVC to the fume line running up to the roof. I'm hoping he can branch off the cast iron line in my attic with PVC as well. I think I'm going to have him run individual ones to the sink and tub instead of sharing one. The plumber is a close friend and all I'm paying for is the PVC. All the copper lines and connectors are free!

I did read somewhere that when I go to frame the walls that I should use 2X6 in order to have room for the plumbing lines. The main cast iron line that we replaced I bought 3" type 40 and I have 2" type 40 that I guess he is going to use to run to sink and tub. The 2X6 would give more room for insulation, but will shorten the room and I imagine when it comes time to getting to the window I'm going to have to build a wide window seal and line the insides with what ever size I need. The molding I'm going to use is the old historic molding that I'm currently stripping and staining. I love the old wood work in this house and would never replace it with the newer crap at Lowe's.

So if you could answer one last question for me I would be forever thankful. If my plumber runs 2" PVC to the sink and tub do you think it would be okay to frame using 2x4's or should I go with the 2x6 frame?

Thanks in advance.:)

keith3267
Re: Interior brick walls covered with plaster or concrete I think....Need avise!

You can use 2x4's for the wet wall of the sink and tub. If this is an exterior wall, I would bias the supply pipes to the interior and get plenty of insulation between them and the outside wall, otherwise you will have a freeze problem. If you are using an enclosed cabinet as a vanity, you should use louvered doors so that some warm room air can get in there or have a gap at the back.

Glad to see that you are going with vent (fume) lines. The issue that I have with the mechanical ones is that they become a maintenance item. They have to be replaced every 10 or 20 years or so. The vent lines are not a future maintenance item. Rubber deteriorates over time.

bwalton41073
Re: Interior brick walls covered with plaster or concrete I think....Need avise!
keith3267 wrote:

You can use 2x4's for the wet wall of the sink and tub. If this is an exterior wall, I would bias the supply pipes to the interior and get plenty of insulation between them and the outside wall, otherwise you will have a freeze problem. If you are using an enclosed cabinet as a vanity, you should use louvered doors so that some warm room air can get in there or have a gap at the back.

Glad to see that you are going with vent (fume) lines. The issue that I have with the mechanical ones is that they become a maintenance item. They have to be replaced every 10 or 20 years or so. The vent lines are not a future maintenance item. Rubber deteriorates over time.

Keith,

Thanks again for the info. I think there is only one wall that I will have to frame using 2x6's. I definitely don't want pipes freezing.

Thanks again...

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