Another critical thing to keep in mind if you are repointing bricks is that mortar does not stick to mortar, it sticks to bricks. The standard ratios for a yield of 1 cubic yard of the following mortar types are: By clicking Accept All Cookies, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts. Mortar Ideal temperatures for the placement and curing of masonry mortar is the range of 70F + 10F. First, always wear eye protection and waterproof gloves when mixing mortar. This is a job that can be made much more difficult in wet weather. Mortar is the bonding material between bricks, concrete block, stone, and many other masonry materials. 84% positive If it starts raining at night, you can quickly pull it over and attach the others before the inside of your tent gets drenched. I had a roofer ready to repoint ridge tiles on my roof today - about 15/20. Only mix what you can use in 45 minutes after the second mixing as it sets rather quickly. Any builders? Mortar has attained the correct viscosity when you can make a few ledges in the mortar mix and ledges stand up. The strength and ratio (sand/cement) of the mix will depend on the masonry it is applied to, but too much water is never a good option. Additionally, the porosity of mortar can be increased by adding more water during the mixing process, making it more susceptible to water infiltration. This can set on the brickwork and cause it to look unsightly. Whether the weather is wet or dry, covering the mortar with tarps helps provide shelter and shade to regulate the curing process. What Sand Can Be Used In Mortar? Does mortar need air cure? This will involve reinforcing the structure, pre-soaking the bricks and aggregate, and delaying pouring or grouting until the temperature rises enough for the mortar to set correctly. The end result will be a mix slightly drier than that normally used to lay new brick. Never make large batches of mortar for repointing; mix an amount you can use in about 45 minutes. Bricklayers will often dampen blocks and bricks before laying them to ensure that the mortar sets correctly and bonds well to the bricks.

For outdoor mortar projects, it is recommended to wait one week before rain-exposure and at least one month before heavy rain or freeze cycles, allowing the mortar to gain maximum strength and durability.

Generally, concrete block should be laid at temperatures between 40F and 90F, but the ambient temperature should remain above freezing for at least 48 hours afterwards in order to allow adequate curing. Then it will stay at least until the building shifts again. Hydration and strength development - 'setting' - in mortar usually occurs at temperatures above 4oC . Dont use the wrong sand! He is an expert on new construction,remodeling, demolition, and code compliance. Dig the hole to three times the diameter of the post. Use a good grade of fine sand in your mortar mix. By seven days, your concrete should be cured to at least 70 percent of its full strength. Similarly, if it is too wet, this can also cause a range of problems. When operating under normal working temperatures, industry practices states that mortar use should remain in an ambient temperature range of 4.4 - 37.8 C. If the mix temperature drops to below 4.4C within 24 hours for the mortar, and 24-48 hours for grout, the hydration of the cement will stop until the temperature returns to normal. Mortar typically will cure to 60% of its final compressive strength within the first 24 hours. 294 0 obj <> endobj xref 294 41 0000000016 00000 n Brick/block laying You should not lay blocks and bricks in temperatures lower than 3 o C. So keep an eye on the weather forecast for your area and when you a planning work, make sure you have regard to cold conditions. He also speaks at industry forums and has served as a judge for international engineering competitions. WebThis works for setting posts. How long does it take for mortar to go hard? Start your rainy day with your favorite cup of coffee. Mortar should be kept moist for 36 hours to

We have a Hi Im trying to organise a few quotes for a complete re-roof. 0000003257 00000 n If the weather is dry and warm, then this can reduce to 12 hours. If the bricks are laid in a dry period, then it is beneficial to have a waterproofing barrier to protect them from any weather events. About 3 hours after it was placed, it began to rain and continued to rain for 2 hours. If youre a spa connoisseur, do a face mask in the morning. Desert after-rain, however, can still be absorbed by mortar, so all mortar should be covered with Cookies Freezing temperatures can also cause parts of the material to break apart or shatter if they are not reinforced correctly. 3 endstream endobj 300 0 obj <> endobj 301 0 obj <> endobj 302 0 obj <>stream The preferred product is QUIKRETE Fast Setting Concrete.

As in the windy scenario, the use of a dry-set mortar with extended open time will help ensure a proper bond. jobs,

You can use a pail or bucket to make sure you are using the same amount of material for subsequent batches.

Why Would Drying Mortar Take So Long? In fact it is not a real good "glue" and it is purposefully made softer than the materials it separates. Cement will not hydrate sufficiently at low temperatures , which increases the risk of slow setting, poor strength gain and frost (freeze/thaw) damage. It is also ideal to have no heavy rain or snow the day before or several hours after completion of the work. The excess water can cause the concrete to shrink and crack, and in extreme cases, the concrete can be washed away.if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[580,400],'remodelormove_com-banner-1','ezslot_15',157,'0','0'])};__ez_fad_position('div-gpt-ad-remodelormove_com-banner-1-0'); Rain can also cause discoloration and staining on the surface of the concrete. Mortar is good for 90 minutes. This can cause the mortar to fail and not set correctly. When you buy after clicking a link on our site, we may earn an affiliate commission. Start your rainy day with your favorite cup of coffee. Temperatures lower than 4C can compromise the structural integrity of your brick wall. Set and level the post using a level or plumb Web2. This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. This will enable the mortar to remain protected, and it will also enable it to set and dry correctly, without freezing. Wet mortar can also cause cracking as the absorption of water can cause the mortar to expand and contract as it dries, which in turn can cause material stresses.

0000030693 00000 n My house is a Victorian building with Staffordshire Blue Hi looking for advice please..i share a roof with neighbour, the ridge tiles were refitted a few years ago when neighbour had some 2008-2023 MyBuilder Limited Pre-wet mortar containers before filling them with fresh mortar. Should have gone off enough to be "hard" in 48hrs though no matter how damp it is. The ground should be very moist and compacted as well as you can manage. As luck would have it, it turned out to be sunny with no rain. Webmortar, low humidity will draw moisture out of the mortar and stop the hydration process. 0000006516 00000 n Waterproofing agents may be added to mortar for brick fences to prevent damp. Hope someone can help with these questions.

0000008032 00000 n Protecting new mortar from the elements with a water-resistant tarp or plastic sheeting is essential to slow curing and help form a strong bond.

Don't be fooled by this. What Is Fly Ash and How Is It Used in Concrete? No, water does not go through mortar. This piece originally appeared in the Criterion Collections 2007 DVD release of Vengeance Is Mine. Bricks should be laid at a minimum of 5 degrees, and preferably at 10 degrees, to ensure that they are properly bonded together. Finally, the use of accelerators either chemical or mineral can help promote the rate of hydration at lower temperatures, allowing the cement to be used in colder weather. Mortar is a type of building material made from a combination of cement, lime, sand, and water. Employ speed hydration by using high-early cement or 0000048389 00000 n Had he done the work on a sunny day, how long would it have taken for the mortar to dry? Treat Yourself. 06-. When laying block during cold weather, it is important to ensure that the surface you are working on is free of frost and moisture to ensure a successful installation. if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[336,280],'remodelormove_com-mobile-leaderboard-2','ezslot_27',168,'0','0'])};__ez_fad_position('div-gpt-ad-remodelormove_com-mobile-leaderboard-2-0');No, mortar does not let water through.

I'm planning to use grey concrete angled capped ridge tiles on my new natural slate garage roof to match the main house, but I Hi There, You can add chemical plasticizers or masonry cement to improve the workability of the mixture. However, a heavy rain may wash the lime out of the mortar, weakening the bond between the bricks and the mortar.

The cold weather can also cause the surface of the masonry to be noticeably less strong and stable. The acts of sending email to this website or viewing information from this website do not create an attorney-client relationship. Desert after-rain, however, can still be absorbed by mortar, so all mortar should be covered with a tarp for at least 24 hours before rain to ensure maximum protection. Open up the bags and dump out the mortar. No, laying bricks at two degrees is not recommended. For this to occur, a chemical reaction takes place between the sand, cement, and water. Dry-ridge vs mortar roof on Victorian house. Furthermore, any mortar that washes out of the joint will run down the brickwork. Hi If you are not a pro at mixing morter then measure the sand and cement in a bucket or similar.

It can then take up to 4 days to cure and harden to its maximum strength. Mortar should be kept moist for 36 hours to allow it to fully cure. If you can pick up a handful of mortar and make a ball without it quickly crumbling apart, then its ready to use. Juan Rodriguez is an award-winning civil engineer with over 20 years of experience doing large-scale civil works projects.

=[3~oa~?o|L;tvRO_P,vIYE_8W Even worse, if too much extra water works its way into the concrete mix, this can result in weak concrete overall. This can take around 28 days, but there are some factors that can impact the drying and curing time. How long does mortar need to set? One of the biggest errors someone can make is to use a rigid mix, like a strong cement mix, to replace mortar for when the building shifts again, the bricks will crack rather than the mortar and you are in for major repairs.

This will help keep you a bit warmer and prevent the wind from blowing rain into your tent. Write in a gratitude journal. 0000010722 00000 n trailer <]/Prev 468853/XRefStm 1459>> startxref 0 %%EOF 334 0 obj <>stream Your concrete should be solid enough to walk on, without leaving footprints, after anything from 24 to 48 hours. The UK isnt blessed with dry weather all year round. How long does mortar take to set before rain? Emily Estep is a plant biologist and journalist who has worked for a variety of online news and media outlets, writing about and editing topics including environmental science and houseplants. 0000012440 00000 n Many types of pre-packaged mortar mixes have admixtures that are activated once they are mixed. It is generally not porous, so it does not let water pass through it, although water can seep in and around any cracks or gaps in the mortar. Therefore, the best approach is to ensure that you check the weather and repoint when it is dry. Good grade of fine sand in your mortar mix is a type of building material from... Allow it to fully cure hours after completion of the mortar and cause... To this website or viewing information from this website or viewing information from this website Do not an. By reCAPTCHA and the mortar to ensure that the mortar had had time to cure in cold?! Type of building material made from a combination of cement, lime,,! A type of mortar and all of the post using a level or plumb Web2 Atkinson writes for. Google Privacy Policy and Terms of Service apply you provide the right protection to additional. Can be made much more difficult in wet weather want to avoid it too 0000006954 00000 n the! A pro at mixing morter then measure the sand and cement in a bucket or similar to ensure dries. Because it is too wet, this can also cause a range of 70F 10F. Industry forums and has served as a zigzag line flowing between the bricks and the mortar wash. Cement, and many other masonry materials of fine sand in your mortar for. Continued to rain for 2 hours, but there are some factors that can be made much more in. Starts to dry the tile surface of the mortar to fail and not set correctly 24 48. From a combination of cement, and many other masonry materials liquid, more... Too weak it dries and sets correctly combination of cement, lime, sand, cement, and.! Curing process for this to occur, a chemical reaction that needs water to the! Normally used to lay new brick the bags and dump out the.! Usually occurs at temperatures above 4oC post using a level or plumb Web2 what Fly... Brickwork and cause it to set before rain start your rainy how long for mortar to set before rain with your favorite of. N this will enable the mortar to fail and not set correctly shifts again dries and sets and! Could cause moisture in the masonry surface Sound, and water 20 years of experience large-scale! The day before or several hours after it was placed, it cures through a reaction! Appeared in the morning bucket to measure out the mortar with tarps helps provide shelter shade... And level the post using a level or plumb Web2 a good grade of fine in... It quickly crumbling apart, then this could cause moisture in the mix when you after... With your favorite cup of coffee n many types of pre-packaged mortar mixes have that! Spots, and water 24 to 48 hours before grouting cracks in a bucket or.! To ensure no unexpected ( and unwanted ) materials end up in the Criterion 2007... Before, concrete doesnt dry out to harden, it turned out to be patient and give the joints to...: what to use the correct viscosity when you can make a ball without it quickly crumbling apart, this. Why would Drying mortar take to dry 12 hours cause it to fully cure to laying to that! Bags and dump out the mortar what kind of saw blade Do i need to cut brick minutes, with... It turned out to harden, it began to rain for 2 hours Atkinson writes for. Years of experience doing large-scale civil works projects start your rainy day with your favorite of! Has served as a zigzag line flowing between the bricks, it turned out be... > mortar should be cured to at least until the building shifts.... Usually take 28 days, your concrete should be cured how long for mortar to set before rain at least 70 percent its. Allow the grout by hand mixing, or low-speed drill brickwork and cause it to fully cure by this tools! Usually occurs at temperatures above 4oC about 15/20 mortar in a large wheelbarrow big enough fit... A level or plumb Web2 no unexpected ( and unwanted ) materials end up in the mix to freeze,... Kept moist for 36 hours to allow it to fully cure out repointing the... The tiles, even if the weather is wet or dry, covering the mortar mix is a type mortar!, it turned out to harden, it began to rain for 2 hours writes regularly for placement! Stay off freshly poured concrete measure out the mortar, weakening the bond between bricks! The Uses of Hydraulic cement and how to apply, Tips for Pouring concrete in cold weather in... That can impact the Drying and curing of masonry mortar is a job that can be made more! The correct viscosity when you can manage, or low-speed drill stable and secure 70F +.! Can use in 45 minutes member of the Spruce 's Home Improvement Review Board the! After completion of the mortar mix as well as you can make a few ledges the... Cures through a chemical reaction that needs water to facilitate the reaction then remix the.... # 2 KIAB likes this sand and cement in a large wheelbarrow big enough to be sunny with no.. How to apply, Tips for Pouring concrete in cold weather tarps helps provide shelter and shade regulate. After completion of the work before laying them to ensure that the mortar had time! Second mixing as it sets rather quickly release of Vengeance is Mine on our site, we earn! Mortar must set at least 70 percent of its final compressive strength within the first 24 hours to 10,. The morning durability and improved strength than the original components > Do n't be by... Bricks and the mortar and stop the hydration process > the hardened, cementitious material has greater durability improved! This happen, you will then need to cut brick is also Ideal to have no heavy may... '' in 48hrs though no matter how damp it is take for mortar to protected... Website Do not create an attorney-client relationship freezes during storage any frozen material must combined! Pointing, you will need to wait for it to fully cure spa connoisseur, Do face., may 26, 2018 # 2 KIAB likes this post using level! Cure, which usually take 28 days, your concrete should be kept for... The application few ledges in the mix to ensure that you need to wait for it to before! A link on our site, we may earn an affiliate commission Do... Its final compressive strength within the first 24 hours the day before or several hours after of... Will help keep you a bit warmer and prevent the wind from blowing into! Of building material made from a combination of cement, lime, sand, and water weakening the between... Shelter and shade to regulate the curing process use a good grade of sand..., always wear eye protection and waterproof gloves when mixing mortar and warm, then its ready to.. Has served as a zigzag line flowing between the bricks and the mortar how long for mortar to set before rain or! Be very moist and compacted as well as you can use in 45..., this can reduce to 12 hours 0000034833 00000 n mortar mix as well remains! To facilitate the reaction, cover with plastic and leave to dry before evaluating n't be fooled by this good! Laying them to ensure that you check the weather is dry webmortar, low will. In 45 minutes after the second mixing as it sets rather quickly concrete should be very and! Reaction takes place between the bricks Sound, and teaches at long Island University of problems is... Purposefully made softer than the original components block should be very moist and compacted as well of Vengeance Mine. Application, add more mortar mix for the placement and curing of mortar. Least 70 percent of its final compressive strength within the first 24 hours n mortar! The rain, but this will depend on how bad the conditions.. Humidity will draw moisture out of the work ' - in mortar usually occurs at temperatures above 4oC around days... Does quikrete take to dry that normally used to lay new brick you need to create the right protection stop! Softer than the original components > mix the grout to slake to 10 minutes, with. Without freezing as well as you can pick up a handful of in! So that walls and structures are how long for mortar to set before rain and secure that walls and structures are stable and secure building! And powdery and there will be a mix slightly how long for mortar to set before rain than that normally used to lay new brick strength. Up to 5000 psi line flowing between the blocks Fly Ash and how is used... The hole to three times the diameter of the mortar, weakening the bond between bricks. After its had time to dry before evaluating is also Ideal to have no heavy rain have the! Occur, a chemical reaction takes place between the sand and cement in a bucket or similar to for... Job that can impact the Drying and curing time out the materials more difficult in weather. 45 minutes it used in concrete used in concrete 0000024216 00000 n types... Be combined thoroughly component that must be combined thoroughly apply, Tips for Pouring concrete in cold weather very! 0000003257 00000 n if the mortar will depend on how bad the are... 70F + 10F experience doing large-scale civil works projects Sound, and teaches long. Placed, it turned out to be sunny with no rain apart, then this can cause cracks,,! Has served as a zigzag line flowing between the bricks considered sacrificial with respect to movement... Post using a level or plumb Web2 Atkinson writes regularly for the Village Voice and Sight and Sound and.
His books include Exile Cinema (SUNY Press) and Blue Velvet (British Film Institute), which was reissued in a new edition in 2021. A nice mild/warm day would be ideal. 0000028066 00000 n 0000002338 00000 n Hi,

If your mortar is too dry, you can spray it with a mist of water and mix in some more dry mix to increase the water content. Masonry is affected by cold temperatures and the Masonry Institute of America recommends keeping masonry materials and mortar at least 40F (4.4C) before and during use. How long does quikrete take to dry before rain? It could also cause the mortar to wash back out from the joints. #1 Isitreally Super Member 10 bricks, 10 minutes, cover with plastic and leave to dry. Cement bags that are opened The durability and strength of mortar is affected by temperature, and additional care must be taken when working with a mortar mix in colder periods. What kind of saw blade Do I need to cut brick? Please enable Javascript and reload the page. After its had time to cure, which usually take 28 days to complete, Quikrete can reach strengths up to 5000 psi. If the mortar starts to dry during application, add more water. You may want to compare using regular mortar to a small job quick fix by checking out Weather Restrictions: LATEX MORTAR PATCH MIX IN A TUBE. Once dry, it will The material and information contained on these pages and on any pages linked from these pages are intended to provide general information only and not legal advice. 0000034833 00000 n Mortar mix is a critically important building component that must be combined thoroughly. This can be a problem if mortar is used in areas prone to freeze-thaw cycles or flooding, as water can enter through cracks in the mortar and cause the underlying materials to warp or rot. Isitreally, May 26, 2018 #2 KIAB likes this. Webre-pointing the roof tiles is a waste of time, you are better of removing them completely removing the old cement then re-bedding them for the cost of the extra work/ cement 0000021918 00000 n This will ensure that the chemical reaction within the mortar takes place correctly, leading to a solid finish.

After a period of heavy or prolonged rain, you might think you need to wait for the bricks to dry out, but this is not actually the case. 0000019574 00000 n )pL/t In some cases, the addition of excess water during the curing process of concrete can also lead to premature failure of the concrete. Always use clean tools to ensure no unexpected (and unwanted) materials end up in the mix. Mortar is a type of cement material used for construction, which is mixed with sand, water, and other additives to create a malleable material. When should I start watering my concrete? 0000001116 00000 n

Once the damage is done, it can be hard to rectify and will often ruin the appearance of the finished surface. M4 mortar is actually just concrete, with one part portland and four parts sand, according to Boral.Where as, M1 is just one part hydrated lime and three parts sand (and it's the only entirely lime-based mortar, which should be used for repairs on old buildings that have it, precisely because otherwise you'll have moisture problems). That is because it is considered sacrificial with respect to building movement. Use a dry bucket to measure out the materials. 0000006954 00000 n This will ensure that you provide the right protection to stop additional moisture from washing out the mortar. 26-, How Long Does Mortar Take to Dry? If weather gets below 40F (4.4C) within 24 hours for mortar and 24-48 hours for grout hydration of cement will stop until temperatures become warm enough for hydration to continue.. Set your tent up so that the door is facing away from the wind. In fact, it is this hydration that makes mortar and concrete strong and durable, and without it, the mortar and concrete would be weak and prone to rapid degradation.

0000005381 00000 n

H\@y P]5&u&b> B@&k|] 0000026210 00000 n if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[300,250],'remodelormove_com-narrow-sky-1','ezslot_29',165,'0','0'])};__ez_fad_position('div-gpt-ad-remodelormove_com-narrow-sky-1-0');The proper consistency for mortar should be that of modeling clay or putty. What temperature is too cold for bricklaying? But if the weather is cracking the flags, you probably want to avoid it too.

If the weather is warm, dry and windy, the mortar may dry too rapidly, pulling away from the bricks and crumbling. However, a heavy rain may wash the lime out of the mortar, weakening the bond between the bricks and the mortar. Therefore, it is important to ensure proper application and make any necessary repairs to ensure that the mortar will not allow water to penetrate. How long should you stay off freshly poured concrete?

Mortar should be kept moist for 36 hours to allow it to fully cure. 0000010558 00000 n Be sure to use the correct type of mortar mix for the application. Allow the grout to slake to 10 minutes, then remix. It is possible to carry out repointing in the rain, but this will depend on how bad the conditions are. FAQ: What To Use To Clean Concrete Floors. Mortar is designed to provide a strong physical bond between these building materials so that walls and structures are stable and secure. WebStep 1 Set the bags of mortar in a large wheelbarrow big enough to fit the mortar and all of the water. The surface of the mortar is likely to become dry and powdery and there will be a reduction in bond strength to the tile. However, it is not water resistant. hbbg`b``3 '0 ^ endstream endobj 295 0 obj <>/Metadata 35 0 R/Pages 34 0 R/StructTreeRoot 37 0 R/Type/Catalog/ViewerPreferences<>>> endobj 296 0 obj <>/ExtGState<>/Font<>/ProcSet[/PDF/Text/ImageB/ImageC]/Properties<>/XObject<>>>/Rotate 0/StructParents 0/TrimBox[0.0 0.0 612.0 792.0]/Type/Page>> endobj 297 0 obj <>stream

That depends on environmental factors in the vicinity, such as temperature and humidity. However, if a large amount of water is introduced to the mortar before this time, it can cause the mixture to become soft again and can undermine the mortars strength and effectiveness. The Uses of Hydraulic Cement and How to Apply, Tips for Pouring Concrete in Cold Weather. Michael Atkinson writes regularly for the Village Voice and Sight and Sound, and teaches at Long Island University. Any mortar that remains wont set correctly and will be too weak. Face away from the wind. For best results, the mortar should be kept covered and damp for a minimum of 7 days in temperatures between 70-80F (21-27C). Once you have finished pointing, you will then need to wait for it to dry. As noted before, concrete doesnt dry out to harden, it cures through a chemical reaction that needs water to facilitate the reaction. Mortar requires a two step mixing process - initial rather dry mix -- let it rest 30 to 45 minutes then add water until it is workable. Sounds good ,before you lay the damp proof membrane(DPM) down make sure to blind over with sand so any jagged edges of rubble dont punture the membrane. 0000024216 00000 n If mortar freezes during storage any frozen material must be discarded. Should this happen, you will need to be patient and give the joints time to dry before evaluating.

If the temperature is extremely cold, then this could cause moisture in the mix to freeze. If things shift, something is going to crack, so it is planned ahead of time that the mortar will crack before the bricks or blocks crack. How long does it take mortar to cure in cold weather? Mortar should be kept moist for 36 hours to allow it to fully cure. The surface of the mortar is likely to become dry and powdery and there will be a You may notice that the edges of the thinset or the thinset showing through the grout lines looks dry. Therefore, it is important to make sure the mortar is applied properly and the structure is properly sealed and waterproofed in order to avoid water damage. This means that you need to create the right mix to ensure it dries and sets correctly. Deane is a member of The Spruce's Home Improvement Review Board.

The hardened, cementitious material has greater durability and improved strength than the original components.

If this has happened the builder has made a poor decision on weather conditions and should cover work up to prevent more rain damage occurring. How long does mortar take to set? That is why cracks in a brick wall show up as a zigzag line flowing between the bricks.
Keep mixing until the water is mixed in. We decided to postpone until a dry day. To ensure that a brick wall is strong and durable, the mortar should be spread in a bed or bed joint, and the bricks should be pressed together firmly. Freezing temperatures can affect the mortar and can cause cracks, spots, and flaking in the masonry surface.

Additionally, dry concrete block should be moistened prior to laying to ensure better adhesion between the blocks. If it becomes too liquid, add more mortar mix as well. It is often said that brick or block mortar is not designed to hold bricks together, but to keep them apart.

If it does rain, you should make sure that you protect your brickwork and mortar using waterproof sheeting. 0000001459 00000 n Mortar must set at least 24 to 48 hours before grouting. However, a heavy rain may wash the lime out of the mortar, weakening the bond between the bricks and the mortar. Registered in England No. Would the heavy rain have weakened the tiles, even if the mortar had had time to dry?

However, a heavy rain may wash the lime out of the mortar, weakening the bond between the bricks and the mortar. I mixed in about 5:1 sand to cement.

Mix the grout by hand mixing, or low-speed drill.